Compute: {{MATH_49}} {{CMD_50}} We can apply the Second Fundamental Theorem of Calculus and, in order to do that, we first need to compute an indefinite integral. {{MATH_51}} As before, we set {{MATH_52}}, and compute {{MATH_53}}, thinking in terms of differentials. Now we see that {{MATH_54}} Hence {{MATH_55}} This does not look right, since we need to find an antiderivative of the function {{MATH_56}} and our result is a function of {{MATH_57}}. We can easily fix this, by simply substituting {{MATH_58}} with {{MATH_59}}. Therefore, {{MATH_60}} Finally, we can apply the SFTOC {{ENV_61}} {{CMD_62}} {{CMD_63}} In this case, because we used substitution to find the indefinite integral, we did not need to modify the limits of integration when calculating the definite integral. However, we did have the extra step of rewriting the antiderivative back in terms of the original variable. If you follow this method, notice that you are performing two separate calculations. The first uses substitution to calculate the antiderivative (without any limits of integration), then using that result to calculate the definite integral using SFTOC.