Integrating Calc Equations: U-Substitution Solutions

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The discussion focuses on difficulties with integrating two specific equations using u-substitution. The equations in question are ∫√(1 + e^x)dx and ∫(arctan(√t)/√t)dt. Participants suggest trying substitutions like t = √(1 + e^x) and u = √t to simplify the integrals. Additionally, they mention the potential need for integration by parts to solve these problems effectively. Understanding these techniques is crucial for mastering the integration concepts presented in the quiz.
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Okay, I just failed my Calc quiz and I want to know how to do the problems I missed. I failed to integrate two of the three equations that were given. The two I missed were:

\int\sqrt{1 + e^x}dx

\int\frac{\arctan{\sqrt{t}}}{\sqrt{t}}dt

Nothing like this is in our book, I don't know where she gets these problems from. She said we're suppose to use some type of u-substitution but I can't figure out which. Can someone walk me through this?
 
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Try the following substitutions:

t = \sqrt{1+e^x}

u = \sqrt{t}
 
TD said:
Try the following substitutions:

t = \sqrt{1+e^x}

u = \sqrt{t}

You may need to use integration by parts as well.
 
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