The area of the region between the curve y=3x square and the x axis in the interval x=0 to x = b is (b is +ve)

Q. Use a definite integral to find the area of the region between the given curve and the x-axis on the interval $[0,b]$:
$y=\sqrt{b^2-x^2}$

Q. Use a definite integral to find the area of the region between the given curve and the x-axis on the interval $[0,b]$:
$y=3x^2$

Q. Use a definite integral to find the area of the region between the curves $y=x^2+x$ and the $x-$axis on the interval $[1,4]$

Q. In the interval $[0,\frac{\pi }{2}]$ area lying between the curve $y=\tan x,y=\cot x$ and $x$-axis is

Q. Given equation of the curve is $y=sinx$.

Using definite integral, find the area of the region between the given curve and the x-axis in the interval of $[0,\pi ]$.