-1 1 2 - simplelecture.comsimplelecture.com/blogs/wp-content/uploads/2016/03/Maths-Solved... · 2nd...
Transcript of -1 1 2 - simplelecture.comsimplelecture.com/blogs/wp-content/uploads/2016/03/Maths-Solved... · 2nd...
2nd PUC Mathematics Solved Guess Paper-1 www.SimpleLecture.com
Simplelecture.com – India’s Leadings smart learning campus for 10th 11th 12th , IIT ,AIEEE, AIPMT ( All Engineering and Medical Entrance courses )
Solved Guess Paper - 1
II PUC Mathematics
One Mark Questions
1. Give an example of a relation which is reflective and transitive but net symmetric .
Ans.
A = { 1 , 2, 3}
R = { (1 , 1), (2, 2), (3, 3), (2, 3)}
2. Find the principal value of cos-1
1-
2
Ans. π 3π
π =4 4
3. Constant a 2 2 matrix A = [aij] whose element are given by aij =i
j
Ans.
11
A = 2
2 1
4. If
2 3A =
-1 2 find |2A |
Ans. | A | = 4 + 3 = 7
| 2 A | = 4 |A| = 28
5. If y = e3 log x then show that
2dy= 3x
dx.
Ans.
3logx
3
2
y =
y = x
dy= 3x
dx
2nd PUC Mathematics Solved Guess Paper-1 www.SimpleLecture.com
Simplelecture.com – India’s Leadings smart learning campus for 10th 11th 12th , IIT ,AIEEE, AIPMT ( All Engineering and Medical Entrance courses )
6.
2
2
1Evaluate x 1- dx
x
Ans.
2
3
(x -1)dx
x- x + c
3
7. Define the feasible region in L . P . P
Ans. A region which is common to all the constraints
8. Find the unit vector in the direction a = 2i + 3j+ 6K
of the vector .
Ans. 2i + 3j + 6K 2i + 3j + 6Kn = =
74 + 9 + 36
9. Find the direction ratio of the line x -1 2Z + 3
= 3y =2 4
Ans.
3Z +
x -1 y 2= =12 2
3
Direction of ratio 1
(2, , 2)3
.
10. If p(F) = 0.6 and P(E nF) = 0.2 find P(E / F) .
Ans. P(EnF) 0.2 1P(E / F) = = =
P(F) 0.6 3
PART – B
Two Mark Questions
11. Define binary operation on the set verify. whether the operation defined m Z by a
b = ab + 1 is binary or not .
Ans. A function : A A A de fined by (a, b ) = a b is called a binary
operation an a set A .
Given ab = ab + 1 on Z
2nd PUC Mathematics Solved Guess Paper-1 www.SimpleLecture.com
Simplelecture.com – India’s Leadings smart learning campus for 10th 11th 12th , IIT ,AIEEE, AIPMT ( All Engineering and Medical Entrance courses )
on Z is a function.
is a binary operation on Z
12. Write
-1
2
1cot
x -1
, x > 1 in the simplest form
Ans .
Put x = sec = sec-1
x
-1
2
-1
2
-1
-1
-1
1cot
x -1
1=cot
sec θ -1
1=cot
tan θ
=cot cotθ
= θ
= sec .x
13. Find the equation of line passing through the points (3 , 2) and (-1 , -3) by using
determinants.
Ans. Equation of the line is 1 1
2 2
x y 1
x y 1 = 0
x y 1
x y 1
3 2 1 = 0
-1 -3 1
x(2+3) –y (3+1)+1(-9+2) = 0
5x – 4y -7 = 0
2nd PUC Mathematics Solved Guess Paper-1 www.SimpleLecture.com
Simplelecture.com – India’s Leadings smart learning campus for 10th 11th 12th , IIT ,AIEEE, AIPMT ( All Engineering and Medical Entrance courses )
14. Show that 2 tan-1
x = sin -1
2
2x
1 + x , | x | 1
Ans. Let tan -1
x = = 1 x = tan
2
2tanθsin 2θ =
1 + tan θ
-1
2
-1 -1
2
2xsin(2 + tan x ) =
1 + x
2x2tan x = sin
1 + x
15.
3
-1 3x - x -1 1If y = tan < x <
1- 3x2 3 3
Ans.
3
-1
2
3x - xy = tan
1- 3x
y - = 3 tan x
2
dy 3=
dx 1 + x
16. Find dy
dx if sin
2 x + cos
2 y = K1 where K is constant
Ans sin2
x + cos2 y = K
2sin x + cos2 y = K
2 sin x + cos x + 2cos y - siny
dy -2sin x cos x=
dx -2 sin y cos y
sin2x=
sin 2y
17. If the radius of a sphere is measured as 7cm with an error of 0.02m.then find the
approximate at error in calculating its volume
Ans. given r = 7 cm , r = 0.02
2nd PUC Mathematics Solved Guess Paper-1 www.SimpleLecture.com
Simplelecture.com – India’s Leadings smart learning campus for 10th 11th 12th , IIT ,AIEEE, AIPMT ( All Engineering and Medical Entrance courses )
34V = πr
3
dvdv = Δ r
dr
4=
3π × 3
2
2
3
r × Δr
= 4πr × Δr
= 4π × 49× 0.02
= 3.92πm
18. 2
cos 2xEvaluate dx
(cos x +sin x )
Ans.
2
2
2
cos 2xdx
(cos x + sin x )
cos2 x -sin 2xdx
(cos x +sin x )
(cos x + sin x)(cos x -sin x)dx
(cos x +sin x)
cos x -sin xdx
cos x +sin x
= log | cos x + sin x / + C
19. -1
Evauate tan x dx
Ans.
2nd PUC Mathematics Solved Guess Paper-1 www.SimpleLecture.com
Simplelecture.com – India’s Leadings smart learning campus for 10th 11th 12th , IIT ,AIEEE, AIPMT ( All Engineering and Medical Entrance courses )
-1
-1
-1
2
-1
2
-1 2
2
2
I = tan x dx
= tan x ×1dx
1= tan x× x - x× dx
x
1 2x= x tan x - dx
2 1 + x
1= xtan x - log | 1 + x | + c
2
1= x tan x - log | 1 + x | +c
2
= x tanx - log | 1 + x | +c
20. Find the projection of the vector i + 3j + 7k on the 7i – j+8k
Ans.
let a = i + 3 j + 7k b = 7 i - j + 8K
a .bpropcehion fa on b =
| b |
7 - 3 + 56=
49 + 1 + 64
60=
114
21. Find the area of parallelogram whose adjacent sides are given by the vectors
a = 3i + j+ 4K and b - i - j+ k
Ans. Area g a parallelogram = a b
Ans. i j k
a × b = 3 1 4
1 -1 1
= I (1+4) -j(3 - 4) + k (-3 -1)
= 5i +j – 4k
a×b = 25 +1+16 = 42
Area of a parallelogram = 42 sq. units .
22. Find the distance of a point ( 21 51 -7) from the plane r . (6i - 3j+ 2k) = 4
Ans. Given plane in Cartesian form is 6x – 3y =+2z = 4
2nd PUC Mathematics Solved Guess Paper-1 www.SimpleLecture.com
Simplelecture.com – India’s Leadings smart learning campus for 10th 11th 12th , IIT ,AIEEE, AIPMT ( All Engineering and Medical Entrance courses )
6(2) - 3(5) + 2(-7) - 4Distance =
36 + 9 + 4
12 -15 -14 - 4=
7
-21=
7
= | - 3|
= 3 units
23. Find and the order and the degree of the differential equation 3 2
3 2
d y d y dy+ + = 0
dx dx dx
Ans. Order = 3, degree = 1
24. Given that the event A and B are such that P(A) = 1
2, P(AB)= 3
5 and P(B) = K,
find K if A and B are independent .
Ans.
P(AB) = P (A)P(B)
3 1= K
5 2
6K =
5
PART – C
Three Mark Questions
25. Show that to relation R in the set of all integers Z defined by R = { (a. b) : 2 divides
a – b} is an equivalence relation .
Ans.
(a) Reflective relation :
2 divides a – a ( a , a ) G R
R is reflective
(b) Symmetric relation
2nd PUC Mathematics Solved Guess Paper-1 www.SimpleLecture.com
Simplelecture.com – India’s Leadings smart learning campus for 10th 11th 12th , IIT ,AIEEE, AIPMT ( All Engineering and Medical Entrance courses )
( a, b) R 2 divides a – b
2 divides b – a
( b , a)R
R is symmetric
(c) Transitive relation
(a , b ) and (b, c) R 2 divides a –b and 2 divides b – c
2 divides a – b+ b – c
2 divides a – c
( a , c) R
R is transitive
R is an equivalence relation.
26.
-1 2 cos x - 3sin x 2Simplify : tan , tan x > - 1.
3cos x + 2 sin x 3
Ans.
-1
-1 -1
-1
÷ Nr and Dr by 3cos x
2- tan x
3= tan2
1 + tan x3
2= tan - tan tan x
3
2= tan - x
3
27. Express matrix
1 2A =
2 -1as the sum of a symmetric and skew - symmetric matrix .
Ans
2nd PUC Mathematics Solved Guess Paper-1 www.SimpleLecture.com
Simplelecture.com – India’s Leadings smart learning campus for 10th 11th 12th , IIT ,AIEEE, AIPMT ( All Engineering and Medical Entrance courses )
.
1
1
1
1 1
1 2A =
2 -1
1 2 1 2 2 4A + A = + =
2 -1 2 -1 4 -2
1 2 1 2A - A = -
2 -1 2 -1
0 0=
0 0
1 1A = (A + A )+ (A - A )
2 2
2 4 0 01 1= +
4 -2 0 02 2
1 2 0 0= +
2 -1 0 0
28. Prove that if the function is differentiable at a point C then it is also continuous at
that point.
Ans. since f is differentiable at c , we have
x c
x c x c
x c x c x c x c
1
x c
f(x) - f(c)lim = f ;(c)
x - c
But for x c we have
f(x)- f(c)f(x)- f(c) = (x - c)
x - c
f(x)f(c)lim f(x) - f(c) = lim (x - c )
x - c
f(x) - f(c)limf(x) - limf(c) = lim lim(x - c)
x - c
= f (c)(o)
= o
lim f(x) = f (c)
Hencef is continous at x = c
29. Verify mean value theorem for the function fx) = x2 – 4x - 3 in the interval [ 1, 4].
Ans. f(x) is continuous in [ 1 , 4 ] and differentiable in (1 , 4) .
f(a) = f(1) = 1-4-3 = 0
f(b) = f(4) = 16-16-3 = -3
f1 (x) = 2x-4
f1( c)= 2c – 4
By mean value tacorem
2nd PUC Mathematics Solved Guess Paper-1 www.SimpleLecture.com
Simplelecture.com – India’s Leadings smart learning campus for 10th 11th 12th , IIT ,AIEEE, AIPMT ( All Engineering and Medical Entrance courses )
1f(b) - f(a)= f (c)
b - a
-3 - 0= 2c - 4
4 -1
-3= 2c - 4
3
-1 = 2c - 4
2c = 3
3c = c (1, 4)
2
30. Find the equation of tangent to the curve given by x = a sin3 t, y = b cos
3 t at a point
where t = π
2 .
Ans. Equation of tangent is y - y1 = m (x – x1) x1 = a sin3π
2 = a (1) = a .
y1= b cos 3
π
2 = b(0) = 0
2
2
dy dy / dt 3bcos t × -sint= =
dx dx / dt 3asin t ×cost
bcos t= -
a sin t
b= - cot t
a
dy π -b π -b/ t = = cot = = m
dx 2 a 2 a
-btangent s y = (x - a)
a
Contunetion q.
31. 2
x + 2Evaluate dx
2x + 6x + 5
Ans.
2nd PUC Mathematics Solved Guess Paper-1 www.SimpleLecture.com
Simplelecture.com – India’s Leadings smart learning campus for 10th 11th 12th , IIT ,AIEEE, AIPMT ( All Engineering and Medical Entrance courses )
2
2 2
2
2
2
dPut x + 2 = m (2x + 6x + 5)+ n
dx
x + 2 = m(4x + 6) + n
x + 2 = 4mx + 6m + n
4m = 1 6m + n = 2
1 1m = 6× + n = 2
4 4
3+ n = 2
2
3n = 2 -
2
1n =
2
52x + 6x + 5 = 2 x + 3x +
2
3 9 5= 2 x + - +
2 4 2
3 -9 + 10= 2 x + +
2 4
3 1= 2 x + +
2 4
3= 2 x +
2
2 2
2
2 2 2
1+
2
d2x + 6x + 5
x + 2 1dxdx = m dx + n dx2x + 6x + 5 2x + 6x + 5 2x + 6x + 5
2
2 2 2
d(2x + 6x + 5)
1 1 1dx= dx + dx4 2x + 6x + 5 2 3 1
2 x + +2 2
2 -1
3x +
1 1 2= log 2x + 6x + 5 + + tan + c14 4
2
2nd PUC Mathematics Solved Guess Paper-1 www.SimpleLecture.com
Simplelecture.com – India’s Leadings smart learning campus for 10th 11th 12th , IIT ,AIEEE, AIPMT ( All Engineering and Medical Entrance courses )
2
2 2 2
2 -1
d(2x + 6x + 5)
1 1 1dx= dx + dx4 2x + 6x + 5 2 3 1
2 x + +2 2
1 1= log 2x + 6x + 5 + + tan (2x + 3) + c
4 4
32.
x 1 + sin x
Evaluate e dx1 + cos x
Ans.
x
x
x
2 2
x 2
x 2
x x 1
x
1 + sin xe dx
1 + cos x
1 sin x= e + dx
1 + cosx 1 + cos x
x x2sin cos
1 2 2= e + dxx x
cos 2cos2 2
1 x x= e sec + tan dx
2 2 2
x 1 x= e tan + sec dx
2 2 2
n= e tan + c e (f(x) + f (x) dx
2
= e ×f(x) + c
33. Find the area boundary by parabola y2 = 4x and the line y = 2x .
Ans. y2 = 4x
(2x)2
= 4x
4x2-4x= 0
4x (x-1) = 0
x = 0 or y = x = 1
y = 0 or y = 2
2nd PUC Mathematics Solved Guess Paper-1 www.SimpleLecture.com
Simplelecture.com – India’s Leadings smart learning campus for 10th 11th 12th , IIT ,AIEEE, AIPMT ( All Engineering and Medical Entrance courses )
The f intersection are (0 , 0 ) and ?(1 , 2)
1
0
1
2
0
1
0
13/2
0
1 1
2
0 0
12
0
1 2
y dx
2 x dx y = 4x y = 2 x
3x
2= 23
2
4= x
3
4= 1- 0
3
4=
3
Δ = y dx = 2x dx
x= 2
2
4=1 - 0 = 1 Required Area = -1 A - A
3
1= s.q units .
3
34. Three vectors a, b ,c
are such that a + b + c = 0
and
a =1, | b|= 4, c = 2 find a ,b + b .c + c .a
Ans.
2 22 2
a + b +c = a + | b | - | c | (a . b +b .c +c .a )
0 = 1+ 16+ 4+ 2(a .b + b . c + c . a)
0 = 21+ 2(a .b + b.c + c . a )
-21a .b + b .c + c .a =
2
35. a.= 2i - 3j+ 4k,b = i + 2j- 3k and c= 3i + 4j- k then find a a×b .c
Ans.
2 -3 4
a . b ×c = 1 2 -3
3 4 -1
2nd PUC Mathematics Solved Guess Paper-1 www.SimpleLecture.com
Simplelecture.com – India’s Leadings smart learning campus for 10th 11th 12th , IIT ,AIEEE, AIPMT ( All Engineering and Medical Entrance courses )
=2(-2 +12) +3 (-1+9)+4(4 – 6)
= 2 (10)+3(8) +4 (-2)
= 20+24-8
= 36
Since
a .(10) + 3(8) + 4(-2)
= 20 + 24 - 8
= 36
Since a .(b×c) = a×b .c
(a×b) . c = 36
36. Find the shortest distance between the lines.
r = i + j + (2i - j + k)and
r = 2i + j - K + M(3I - 5j + 2K)
Ans. Shortest distance = 2 1 1 2
1 2
(a - a ). a ×b
| b ×b |
2 1a . a = i - K
1 2
1 j k= i(-2 + 5) - j(4 - 3) + k(-10 + 3)
b ×b = 2 -1 1= 3i - j - 7k
3 -5 2
37. From the differential equation of the family of circles touching the x – axis at origin .
Ans. 2 1 1 2(a - a ). b ×b = (1)(3) + (0)(-1) + (-1)(-7)
= 3 + 7
= 10
10
Shortest distance =59
38. An insurance company insured 2000 scooter drivers, 4000 car drivers and 60000
truck drivers, the probability of an accident are 0 .01 , 0.03 and 0.15 respectively. One
of the insured person meets with an accident. What is the probability that he is a
scooter driver?
Ans. E1 : An event is insured scooter drivers .
E2 : An event of insured car drivers .
E3 : An event of insured truck drivers .
A : An event of insured getting accident .
2nd PUC Mathematics Solved Guess Paper-1 www.SimpleLecture.com
Simplelecture.com – India’s Leadings smart learning campus for 10th 11th 12th , IIT ,AIEEE, AIPMT ( All Engineering and Medical Entrance courses )
1
2
3
1
2
3
1
1 1
1
1 1 2 2 3 3
2000P(E ) =
12000
4000P(E )=
12000
6000P(E ) =
12000
P(A / E ) = 0.01
P(A / E ) = 0.03
P(A / E ) = 0.15
P(E / A) = ?
P(E )P(A / E )P(E / A) =
P(E )P(A / E ) + P(E )P(A / E ) + P(E )P(A / E )
1
1
2000× 0.01
12000P(E A ) =2000 4000 6000
× 0.01 + × 0.03 + × 0.1512000 12000 12000
2× 0.01=
2× 0.01 + 4× 0.03 + 6× 0.15
1=
1 + 2× 3 + 3×15
1=
1 + 6 + 45
1=
52
PART - D
Five Mark Questions
39. Let f = N R defined by f(x) = 4x2
+ 12x +15, show that f = N S1 where S is the
range of the function is invertible . Also find f -1
.
Ans.
(i)one – one function
1 2
2 2
1 1 2 2
2 2
1 2 1 2
F(x ) = f(x )
4x + 12x + 15 = 4x + 12x + 15
4x - 4x + 12x -12x = 0
2nd PUC Mathematics Solved Guess Paper-1 www.SimpleLecture.com
Simplelecture.com – India’s Leadings smart learning campus for 10th 11th 12th , IIT ,AIEEE, AIPMT ( All Engineering and Medical Entrance courses )
2 2
1 2 1 2
1 2 1 2 1 2
1 2 1 2
1 2 1 2
1 2
÷ 4
x - x + x - x = 0
(x + x )(x - x ) + (x - x ) = 0
(x - x )(x + x + 1) = 0
x - x = 0 or x + x + 1 = 0
x = x N
f is one - one function
(ii) onto function for every y Co – domain then there exists x co – domain such
that
2
2
2
2
2
f(x) = y
4x2 + 12x + 15 = y
154 x2 + 3x + = y
4
3 9 154 x + - + = y
2 4 4
34 x + - 9 + 15 = y
2
34 x + + 6 = y
2
34 x + = y - 6
2
3 y - 6x + =
2 4
y - 63 3x + = -
2 2 2
y - 6 - 3x = domain
2
f is onto
F is objective
F is invertible
T o find f – 1
Consider x = y - 6 - 3
2
2nd PUC Mathematics Solved Guess Paper-1 www.SimpleLecture.com
Simplelecture.com – India’s Leadings smart learning campus for 10th 11th 12th , IIT ,AIEEE, AIPMT ( All Engineering and Medical Entrance courses )
-1
-1
y - 6 - 3f (y) =
2
x - 6 - 3f (x) =
2
40. Verify the equations (B+C) A = BA + CA
1 2 3 1 1 2 1 0 -1
If A = 2 3 1 , B = 1 2 1 , C = -1 1 0
3 1 2 2 1 1 1 -1 0
Ans.
1 1 2 1 0 -1
B + C = 1 2 1 + -1 1 0
2 1 1 -1 -1 0
2 1 1
= 0 3 1
3 0 1
2 1 1 1 2 3
(B + C) A = 0 3 1 2 3 1
3 0 1 3 1 2
2 + 2 + 3 4 + 3 + 1 6 + 1 + 2
= 0 + 6 + 3 0 + 9 + 1 0 + 3 + 2
3 + 0 + 3 6 + 0 + 1 9 + 0 + 2
7 8 9
= 9 10 5 (1)
6 7 11
1 1 2
BA =
1 2 3
1 2 1 2 3 1
2 1 1 3 1 2
1 + 2 + 6 2 + 3 + 2 3 + 1 + 4
= 1 + 4 + 3 2 + 6 + 1 3 + 2 + 2
2 + 2 + 3 4 + 3 + 1 6 + 1 + 2
9 7 8
= 8 9 7
7 8 9
1 0 -1 1 2 3
CA = -1 1 0 2 3 1
1 -1 0 3 1 2
2nd PUC Mathematics Solved Guess Paper-1 www.SimpleLecture.com
Simplelecture.com – India’s Leadings smart learning campus for 10th 11th 12th , IIT ,AIEEE, AIPMT ( All Engineering and Medical Entrance courses )
1 + 0 - 3 2 + 0 -1 3 + 0 - 2
= -1 + 2 + 0 -2 + 3 + 0 -3 + 1 + 0
1- 2 + 0 2 - 3 + 0 3 -1 + 0
-2 1 1
= 1 1 -2
-1 -1 2
9 7 8 -2 1 1
BA +CA = 8 8 7 + 1 1 -2
7 9 9 -1 -1 2
7 8 9
= 8 10 5 (2)
9 7 11
from (1) and (2)
(B + C) A = BA + CA
41. Solve the equations x – y + 3z = 10, x – y = - 22 x + 3y + 4z = 4 by Matrix Method .
Ans.
1 -1 3 x 10
A = 1 -1 -1 X = y B = -2
2 3 4 z 4
| A| =1(-4+ 3) + 1)(4 + 2) + 3(3 + 2)
= -1+ 6+ 15 = 20
-(-4 + 3) -(4 + 2 +(3 + 2)
Co -factor matrix = -(-4 - 9) +(4 - 6) -(3 + 2)
+(1 + 3) -(-1 - 3) +(-1 + 1)
-1
-1 -6 5
= 13 -2 -5
4 4 0
-1 -6 5
adj A = 13 -2 -5
4 4 0
1A = adjA
| A |
2nd PUC Mathematics Solved Guess Paper-1 www.SimpleLecture.com
Simplelecture.com – India’s Leadings smart learning campus for 10th 11th 12th , IIT ,AIEEE, AIPMT ( All Engineering and Medical Entrance courses )
Ans.
-1
-1
-1 13 41
= -6 -2 420
5 -5 0
X = A B
-1 13 4 101
A = -6 -2 4 -220
5 -5 0 4
-10 -26 +161
= -60 +4 +1620
50 +10 +0
-201
= -4020
60
-1
= -2 x = 1, y = - 2 , z = 3
3
42. If g = Ae mx
+ Be nx
+ then prove that 2
2
d y dy- (m + n) + mn y = 0
dx dx
Ans.
mx nx
mx nx
2
2 2
2
2
2
2 mx 2 nx mn nx mx nx
2 mx 2 nx 2 mx nx mx
2 nx mx nx
y = Ae + Be
dymAe + n Be
dx
d y= m Aemx + n Benx
dx
d y dyLHS = - (m + n) + mny
dx dx
= m Ae + n Be - (m + n)(mAe + nBe ) + mn(Ae + Be )
= m Ae + n Be - m Ae - mn Be - nm Ae
-n Be + mn Ae + mn Be
= 0 = RHS
2nd PUC Mathematics Solved Guess Paper-1 www.SimpleLecture.com
Simplelecture.com – India’s Leadings smart learning campus for 10th 11th 12th , IIT ,AIEEE, AIPMT ( All Engineering and Medical Entrance courses )
43. A ladder 5 m long is leaning against a wall. The bottom of the ladder is pulled along
the ground away from the wall at the rate of 2 cm / sec . how fast is its height on the
wall decreasing when the foot of the ladder is 4 m away from the wall?
Ans.
2 2 2
2
dy= 2cm / sec
dt
dy= ? x = 4 m
dt
x + y = 5
16 + y = 25
2
2
2 2 2
y = 25 -16
y = 9
y = 3
x + y = 5
dx dy2x + 2y = 0
dt dt
÷2
dx dyx + y = 0
dt dt
dy4(2) + (3) = 0
dt
dy -8= cm / sec
dx 3
44. Find the integeral of2 2
1
x - a
with respect to x and hence evaluate 2
1dx
x - 2x
Ans.
2nd PUC Mathematics Solved Guess Paper-1 www.SimpleLecture.com
Simplelecture.com – India’s Leadings smart learning campus for 10th 11th 12th , IIT ,AIEEE, AIPMT ( All Engineering and Medical Entrance courses )
2 2 2
2 2
xLet I = Put x = a sec θ = sec θ
a
dx a secθ tanθ dθ
a secθ tanθdθI =
a sec θ - a
a sec θtanθ dθ=
a sec θ-1)
asecθ tan θ= dθ
atanθ
= sec θ dθ
2
2 2
2 2
2 2
2 2 1
2 2 2
2 2 2
2
= log sec θ + tanθ +c
= log secθ + sec θ -1 + c
x x - a= log + + c
a a
x + x - a= log + c
a
= log x + x - a - log a +c
I = log x + x - a + c
Consider x - 2x = (x -1) -1
1 1dx = dx
x - 2x (x -1) -1
= log x -1 + x - 2x + c
45. Using integration find the area bounded by the curve x2 – y
2 = 16 and the parabola y
2
= 6x.
Ans.
X2 +y
2 = 16
X2 +6x = 16
X2
+6x - 16 = 0
2nd PUC Mathematics Solved Guess Paper-1 www.SimpleLecture.com
Simplelecture.com – India’s Leadings smart learning campus for 10th 11th 12th , IIT ,AIEEE, AIPMT ( All Engineering and Medical Entrance courses )
X2 +8x – 2x – 16 = 0
X(x+8) -2(x+8) = 0
(x+8)(x-2)-= 0
X = - 8 or x = 2
2
2
0
2
3/2
0
b n dx y = 6x
y = 6 x
x=
3
2
4
2 2 2
2
42
2 2 -1
2
-1 -1
2 6= 8 -0
3
8 3=
3
A = 4 - x dx
x 4 x= 4 - x + sin
2 2 4
16 1= 0 + sin 1 - 12 + 8sin
2 2
π π= 8× - 12 - 8×
2 6
4π= 4π - 12 -
3
1 2
8π- 2 3
3
Required area
= 2 A + A
8 3 8π= 2 + - 2 3
3 3
2 3 8π= 2 +
3 3
4= 3 + 4π Sq. units
3
2nd PUC Mathematics Solved Guess Paper-1 www.SimpleLecture.com
Simplelecture.com – India’s Leadings smart learning campus for 10th 11th 12th , IIT ,AIEEE, AIPMT ( All Engineering and Medical Entrance courses )
46. Derive the equation of the line in space passing through a point and parallel to a
vector both in the vector and Cartesian form .
Ans.
(a) Vector form
Let a plane be passing through a point A (a )
And parallel to a given vector b
p(r )
Be any point on a line .
AP | | b
AP = λ b
op - OA = λb
r - a = λ b
r = a = λ (1)
(b)Cartesian form
1 1 1
Let r = xi + yj + zk
a = x i + y j + z k
b = ai + bj + ck
Using equation (1)
1 1 1
1 1 1
1 1 1
xi + yj + zk = (x i + y j + z k) + λ(ai + bj + ck)
xi + yj + zk = (x aλ)i + (y + bλ)j + (z + cλ)k
comparing efficients f , i, j,k
x = x + aλ,y = y + bλ,zzz + cλ
Elimineting λfrom above equations
1 1 1x - x b - b z - z= =
a b c
2nd PUC Mathematics Solved Guess Paper-1 www.SimpleLecture.com
Simplelecture.com – India’s Leadings smart learning campus for 10th 11th 12th , IIT ,AIEEE, AIPMT ( All Engineering and Medical Entrance courses )
47. Solve the differential equation x log x dy 2
+ y = log xdx x
Ans.
2
1dx
log(log x)x log x
2
-2
-1 -1
2
dy 2x log x + y = log x
dx x
÷ x log x
dy y 2+ =
dx log x x
I.F =e = e = log x
Solution
2y = log x = log x dx
x
= 2 log x × x dx
1= 2 log x ×(x ) - -x × dx
x
-log x 1= 2 + dx
x x
-log x 1= 2 + - + c
x x
-2 log x 1y log x = - + c
x x
-y =
2 1 c- +
x x log x log x
48. A pair of dice is thrown 4 times . if getting a doublet is considered a success find
the probability of two successes .
Ans.
2nd PUC Mathematics Solved Guess Paper-1 www.SimpleLecture.com
Simplelecture.com – India’s Leadings smart learning campus for 10th 11th 12th , IIT ,AIEEE, AIPMT ( All Engineering and Medical Entrance courses )
2 2
2
2
6 1 1 5n = 4 , p = = ,q = 1- =
36 6 6 6
5 1p (x = 2 )4c
6 6
4=
× 3
22 2
25 1× ×
6 6×1
25=
216
PART - E
Ten Mark Question
49.
a
0a
a
2 f(x)dx if f is even
(a)Prove that f(x)dx = 0
0 if f is odd
1 + a 1 1
(b) prove that 1 1 + b 1 = ab + bc + ca + abc
1 1 1 + c
Ans
.
a
-a
a a
-a 0
0
-a
LHS = f(x)dx
= f(x)dx + f(x)dx (1)
consider f(x)dx
put x = - t
dx = - dt
2nd PUC Mathematics Solved Guess Paper-1 www.SimpleLecture.com
Simplelecture.com – India’s Leadings smart learning campus for 10th 11th 12th , IIT ,AIEEE, AIPMT ( All Engineering and Medical Entrance courses )
0 0
-a a
a
0
a
0
x = - a r = a
x = 0 t = 0
f(x)dx = f(-t)(-dt)
= f(t)dt
= f(-x)dx (2)
f(-x) = f(x) f is even
(3)
f(-x)= -f(x) if f is odd
a a a
0 0 0
using (1) , (2) and(3)
LHS = f(x)dx + f(x)dx = 2 f(x)dx if f is even
a a
0 0
a
a
0
0
π
9 92
LHS = -f(x)dx + f(x)dx = 0 if f isodd
2 f(x)dx if f (x) isevenf(x)dx =
0 if f(x)x) is odd
tan x dx = 0 tan x is a odd
-π
2
1 1 2 2 2 3
1 + a 1 1
(b) LHS = 1 1 + b 1
1 1 1 + c
R R R and R R R
a -b 0
= o b -c
1 1 1 + c
= a(b + bc + c)+ b(o + c) + o
= ab + abc + ac + bc
= ab + bc + ca + abc
= RHS