Definite Integration Question 30

Question: The area formed by triangular shaped region bounded by the curves $ y=\sin x,y=\cos x $ and $ x=0 $ is

[MP PET 2000]

Options:

A) $ \sqrt{2}-1 $

B) 1

C) $ \sqrt{2} $

D) $ 1+\sqrt{2} $

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Answer:

Correct Answer: A

Solution:

Given required area has been shown in the figure. $ x=\frac{\pi }{4} $ is the point of intersection of both curve
$ \therefore $ Required area = $ \int_0^{\pi /4}{(\cos x-\sin x)dx} $

$ =[\sin x+\cos x]_0^{\pi /4} $

$ =[ \frac{1}{\sqrt{2}}+\frac{1}{\sqrt{2}}-1 ] $

= $ \frac{2}{\sqrt{2}}-1=\sqrt{2}-1 $ .