INTEGRATION USING TRIGONOMETRIC AND HYPERBOLIC SUBSTITUTIONS 407
H
Hence
∫ 3
2
√
(x^2 −4) dx
=
[
3
2
√
5 −2(0.9624)
]
−[0]
= 1. 429 , correct to 4 significant figures
Now try the following exercise.
Exercise 162 Further problems on integra-
tion using the coshθsubstitution
- Find
∫
1
√
(t^2 −16)
dt
[
cosh−^1
x
4
+c
]
- Find
∫
3
√
(4x^2 −9)
dx
[
3
2
cosh−^1
2 x
3
+c
]
- Find
∫ √
(θ^2 −9) dθ
[
θ
2
√
(θ^2 −9)−
9
2
cosh−^1
θ
3
+c
]
- Find
∫ √
(4θ^2 −25) dθ
[
θ
√(
θ^2 −
25
4
)
−
25
4
cosh−^1
2 θ
5
+c
]
- Evaluate
∫ 2
1
2
√
(x^2 −1)
dx [2.634]
- Evaluate
∫ 3
2
√
(t^2 −4) dt [1.429]