# Trig Differentiation

## Homework Statement

how is the differential of 1+tan2(4x)

8*tan(4x)*sec2(4x)

## The Attempt at a Solution

So 1 differentiates to 0 (we can now ignore this)
tan2(4x) differentiates to 2*tan(4x)*sec2(4x)?

BRING POWER FORWARD, DOWN POWER BY 1, DIFFERENTIATE TERM IN BRACKET
by the chain rule?

BRING POWER FORWARD, DOWN POWER BY 1, DIFFERENTIATE TERM IN BRACKET
by the chain rule?

You stated it in your question, but never differentiated the term inside inside the bracket.

$$2 \cdot tan(4x)sec^{2}(4x) \cdot \frac{d}{dx} (4x)~=~$$

Last edited:
hold on
yours goes to 32....
NOT 8...

hold on
yours goes to 32....
NOT 8...

My mistake :tongue: I fixed it in my first post ( coefficient was originally wrong), but my point still holds. You ALSO need to differentiate the 4x.

oh of course
differentiate u2 = 2u
differentiate sec2(4x) is 4*sec(4x)*tan(4x)
multiply differntials to give
2*sec(4x)*4*sec(4x)*tan(4x)

Exactly!!