Where did it go wrong in the following process? Integrate: $\int (e^x + e^{-x})^2 dx$ Step 1: $\int (e^x + e^{-x})^2 dx = \int (e^{2x} + e^{-2x}) dx$ Step 2: $= \frac{1}{2}e^{2x} - \frac{1}{2}e^{-2x} + C$ Step 1 Step 2
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However, the square of a sum is not equal to the sum of the squares. So, the expression should be expanded using the formula (a + b)^2 = a^2 + 2ab + b^2. Show more…
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