Question
Question: Let I<sub>1</sub> = \(\int_{\pi/6}^{\pi/3}\frac{\sin x}{x}\)dx, I<sub>2</sub> = \(\int_{\pi/6}^{\pi/...
Let I1 = ∫π/6π/3xsinxdx, I2 = ∫π/6π/3sinxsin(sinx)dx,
I3 = ∫π/6π/3tanxsin(tanx)dx, then
A
I1< I2< I3
B
I2< I1< I3
C
I3< I1< I2
D
I3< I2< I1
Answer
I3< I1< I2
Explanation
Solution
f(x) = xsinxis a decreasing function and
xsinx > 0 for all x in (0, p)
Since sin x < x < tan x
Ž sinxsin(sinx) > xsinx > tanxsin(tanx) for 6π < x < 3π
\ I2 > I1 > I3