# Check these for me?

• Dec 23rd 2009, 02:38 PM
Morgan82
Check these for me?
1) Find area between the curves of y = 2x and y = x^2 -4x
I got 36

2) Find area between the curves of x^2 and x
I got 1/6

Am I right?
• Dec 23rd 2009, 02:46 PM
dedust
Quote:

Originally Posted by Morgan82
1) Find area between the curves of y = 2x and y = x^2 -4x
I got 36

2) Find area between the curves of x^2 and x
I got 1/6

Am I right?

both are correct
• Dec 23rd 2009, 09:15 PM
integral
I got 36 on the first one, but the second I got 2/3 (Itwasntme)

$\int_{0}^{2}2xdx-\int_{0}^{2}x^2dx=\frac{2}{3}$ (Itwasntme)
• Dec 23rd 2009, 09:20 PM
VonNemo19
Quote:

Originally Posted by integral
I got 36 on the first one, but the second I got 2/3 (Itwasntme)

$A_R=\int_0^1(x-x^2)dx=(\frac{x^2}{2}-\frac{x^3}{3})|_0^1=\frac{1}{2}-\frac{1}{3}=\frac{1}{6}$