# 1 1+x The result from the differentiation is dy Derive the formula = dx Solve for dy dx sec²y = 1 Therefore, dy dx dy 1 dx sec²y = = Now, perform a trigonometric substitution for sec ²y. sec²y= dy 1 dx 1 + tan ²y 1 2 1+tan y 1 1+ for the derivative of y = tan =

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