use the fundamental theorem of calculus to evaluate this equation
\[\int\limits_{0}^{2}(3-5x^4)dx\]
so what?!? You actually get to use calculus to find the area or net area now?
lets talk about antiderivatives then
( what goes here)'=3
what can you take the derivative of that will give you 3?
hi again freckles, not exactly sure what to do here
well this is the short cut way to what you have been doing
thank god
we actually did this one day together on a problem
like we had \[\int\limits_{0}^{1}(x^2+1)dx=(\frac{x^{3}}{3}+x)|_0^1=(\frac{1^3}{3}+1)-(\frac{0^3}{3}+0) \\ =\frac{1}{3}+1=\frac{1}{3}+\frac{3}{3}=\frac{4}{3}\] remember this I didn't do the last line because I was leaving the simplifying to you
like just like we found the antiderivative of (x^2+1) in that example we need to find the antiderivative of 3-5x^4
Let c and d be some constant number. The antiderivative of c is cx+d since (cx+d)'=(cx)'+(d)'=c(x)'+0=c(1)+0=c+0=c. That is \[\int\limits_{}^{}c dx=cx+d\] when we have definite integrals like: \[\int\limits_{a}^{b}c dx=cx|_a^b=c(b-a)\] we don't need to put the constant of integration (the one I called d above in; you can put it will just get canceled out)
so, 3x - x^5 is the antiderivative
wow yep that is right
so you have: \[\int\limits_{0}^{2}(3-5x^4) dx =(3x-x^5)|_0^2\]
now I take the anti of F(1) minus the anti of F(0)
2, not 1
the next step is to evaluate that antiderivative expression at the upper limit 2 and then put a minus and then evaluate the antiderivative expression at the lower limit 0
and yes
well the anti if the F since the integrand was the f where you know F'=f
but I think I got what you are saying
ok, here goes
well the ant is the F*
ok I'm ready when you are :p
came up with -58
hmm how did you get that exactly you did this: \[\int\limits\limits_{0}^{2}(3-5x^4) dx =(3x-x^5)|_0^2 \\ =(3 \cdot 2-2^5)-(3 \cdot 0 -0^5)\]
oops, it's actually
-26
sounds beautiful that is actually a net area We know this because |dw:1429484706053:dw|
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