Please help!!!!!! cosx-sin^2x-1

So what is the question and I suspect you have a typo

I always get confused working out this problem because I keep getting the wrong answer. cosine of x- sin squared x-1

and it needs me to write the expression in factored form as an algebraic expression of a single trigonometric function.

sin^2 x = 1 - cos^2 x

cos x - (1-cos^2 x) - 1

cos x - 2 + cos^2 x

cos^2 x + cos x - 2

as you wrote it

perhaps you mean

cos x - (sin^2 x -1)

cos x - (1 -cos^2 x - 1)

cos x + cos^2 x

cos x (cos x + 1)

Where did you get the 1-cosine squared from?

Find an algebraic expression equivalent to the given expression. sine (tan inverse of u/2)

For the problem cosine of x-sine squared x-1 the choices are A)sine squared x, B) (cot x+1)(cot x-1), C) (cos x+2)(sin x-1), D)(sin x+2)(sin x-1)

sin^2 x + cos^2 x = 1 identity

so
sin^2 x = 1 - cos^2 x

(cos/sin +1)(cos/sin-1) = cos^2/sin^2 - 1

====================================
sin[ tan^-1(u/2) ]

right triangle
opposite = u
adjacent = 2

so hypotenuse = sqrt(u^2 +4)
so

sin = u/sqrt(u^2+4)

or [u sqrt (u^2+4)] / (u^2+4)

Thank you for your help. Can you please delete all the questions I have typed in today?