Ok, I was thinking today during my calculus class about taking the integral of a function in a different way. Let's assume for a second that we want to find the area between the function and the y axis, on the interval x = [0, 2] of the function y = 2x.(adsbygoogle = window.adsbygoogle || []).push({});

What I was thinking I could do, is take the integral of y.

(y^2)/2 then substitute 2x in for y, since y = 2x.

(2x)^2 / 2

That would give us the integral between the function and the y axis and we would be able to put in the interval for x.

But it didn't work... I got the wrong answer? Why doesn't this work? I think it should work.

Thanks.

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# Why can't I do this?

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