Area bounded by the curve y=cos ^-1 x and the lines x=0, x=1 is

The correct answer is Option (1) - 1

$y=\cos ^{-1} x,x=0, x=1$

area = $\int\limits_0^1\cos^{-1}xdx$

$\cos y=x$ at $x = 0$, at $x = 1$

$y=\frac{π}{2},y=0$ for principle value

so area = $+\int\limits_0^\frac{π}{2}\cos ydy$

$=[\sin y]_0^\frac{π}{2}=1$ unit