Given that x = ln(sec(2y)) find dy/dx
x = ln (sec (2y))
The chain rule states that d/dy f (g (y)) = f'(g(y)). g'(y)
Here g(y) = sec(2y) so g'(y) = 2.sec(2y).tan(2y)
And f(y) = ln (y) so f'(y) = 1 / y
Thus dx/dy = (1 / sec(2y)) . (2.sec(2y).tan(2y)) = 2.tan(2y)
DH
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