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# INT will not evalaute integral

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## INT will not evalaute integral

(OP)
I have a code that needs to evalaute the arc length equation below:

syms x

a = 10; b = 10; c = 10; d = 10;

fun = 4*a*x^3+3*b*x^2+2*c*x+d

int((1+(fun)^2)^.5)

but all that returns is below:

ans =

int(((40*x^3 + 30*x^2 + 20*x + 10)^2 + 1)^(1/2), x)

Why wont matlab evaluate this integral? I added a line under to check if it would evaulate int(x) and it returned the desired result.

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