How do you differentiate y=ln ln(2x^4)?

1 Answer
Oct 15, 2016

dy/dx=4/(xln(2x^4))

Explanation:

y=ln(ln(2x^4))

Through the chain rule, we see that:

d/dxln(color(red)f(x))=1/color(red)f(x)*d/dxcolor(red)f(x)

So, here, we see that:

dy/dx=d/dxln(color(red)ln(2x^4))=1/color(red)ln(2x^4)*d/dxcolor(red)ln(2x^4)

Note that we will use the same rule again to find d/dxln(2x^4):

dy/dx=1/ln(2x^4) * [d/dxln(color(red)(2x^4))]=1/ln(2x^4) * [1/color(red)(2x^4)*d/dxcolor(red)(2x^4)]

Differentiating 2x^4 through the power rule gives 8x^3:

dy/dx=1/ln(2x^4) * 1/(2x^4) * 8x^3

dy/dx=1/ln(2x^4) * 1/x * 4

dy/dx=4/(xln(2x^4))