Question

I need help proving trigonometric identities. Example: (cot x sin x)(sec x – cos x) = sin2 x

Answer 1

\[\Large (=\frac{cosx}{sinx}sinx)(\frac{1}{cosx}-cosx) \\ \\ \Large =cosx(\frac{1}{cosx}-cosx) \\ \\ \Large =1-\cos^2x \]
Then use an identity

Answer 2

How do I find the reason for each calculation?

Answer 3

For Solving this Question, I would like to ask you that, do you have the detailed conception of : Trigonometric Identity.

Answer 4

@goformit100 No :(

Answer 5

You need to simplify it, and as always, you want to change trigonometry such as
cotx, secx, and cscx into sinx/cosx , 1/cosx, and 1/sinx

Answer 6

to start the problems just convert each trig function to sines and cosines,
as .sam. has done in first step

Answer 7

So change cot x to cos x/sin x and sec x to 1/cos x then why do you cancel sin x?

Answer 8

Also do reasons need to meet a certain standard, I know there needs to be four of them in this case but I don't know why?

Answer 9

@.Sam. Sorry to tag you but I thought you might know the answer to my response question.

Answer 10

You have to cancel in order to simplify it

Answer 11

And how is cos x((1 / cos x) – cos x) able to change to (cos x / cos x) – cos2 x?

Answer 12

You distribute