Verify the identity: (sinx-cosx+1)/(sinx+cosx-1) = (sinx+1)/(cosx)
To simplify the left side of the identity, multiply the numerator and denominator of the left side of the equation by the same factor. Choose the multiplication below that will be most useful in simplifying the left side of the equation.
A. (sinx-cosx+1)/(sinx+cosx-1) * (sinx+1)/(sinx+1)
B. (sinx-cosx+1)/(sinx+cosx-1) * (sinxcosx)/(sinxcosx)
C. (sinx-cosx+1)/(sinx+cosx-1) * (sinx-cosx+1)/(sinx-cosx+1)
D. (sinx-cosx+1)/(sinx+cosx-1) * (sinx+cosx-1)/(sinx+cosx-1)
Distribute in the denominator and combine like terms. Write the answer in terms of sine and cosine.
(sinx-cosx+1)(sinx+1) / (cosx)(sinx-cosx+1)
The expression in the denominator can be simplified to (cosx)(sinx-cosx+1), and the sinx-cosx+1 cancelled, if which identity is applied?
A. cos(-x) = cosx
B. sin^2x - 1 = -cos^2x
C. sin(-x) = -sinx
D. tanx = (sinx)/(cosx)