we can further simplify this:

cotx - tanx = `cosx/sinx - sinx/cosx = (cos^2x-sin^2x)/(sinxcosx)`

multiplying the numerator and denominator by 2, we get

`2(cos^2x - sin^2x)/(2sinxcosx) = (2cos2x)/(sin2x) = 2 cot2x`

we have used the identities: cos2x = cos^2x- sin^2x and sin2x = 2sinxcosx.

hope this helps.

ln(sinx . cos x)

Multiply and divide sinx . cos x by 2

= ln(`(2.sinx .cosx)/(2)` ` ` )

= ln( `sin(2x)/2` )

= [ln( ` ` sin(2x)) - ln(2)]

=[ln( sin(2x))] - [ ln(2)]

differentiation of a constant is 0 is [ ln(2)] =0

=[ln( sin(2x))]

=` ``1/sin(2x) ` sin(2x) = `2cos(2x)/sin(2x) ` = 2 cot(2x) <----- is the answer

Hi

till `d/dx` ln(sinx . cos x)= (cot x- tanx )

the **above** steps are the same .......plz check the attachment for further steps to get the answer which u required