$\text { What is the minimum vertical distance between the parabolas } y = x ^ { 2 } + 4 \text { and } y = x - x ^ { 2 } \text { ? }$

Q18: The graph of the derivative

Q19: The function <span class="ql-formula" data-value="f

Q20: Verify that the function satisfies the

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Q22: A fence <span class="ql-formula" data-value="10

Q24: The function <span class="ql-formula" data-value="f

Q25: The graph of the derivative

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