Math CentralQuandaries & Queries


Question from Katie, a student:

Solve this identity: (1+2sinxcosx)/(sinx+cosx) = sinx+cosx
Thank you !

Hi Katie. There are just two steps to this proof.

First, multiply the left hand side by (sinx + cosx) / (sinx + cosx) leaving the numerator factored, but multiplying out the denominator. Next, use the identity sin2(x) + cos2(x) = 1 to simplify the denominator.

Hope this helps,
Stephen La Rocque

About Math Central


Math Central is supported by the University of Regina and The Pacific Institute for the Mathematical Sciences.
Quandaries & Queries page Home page University of Regina PIMS