Question:

Cos/1- tan + sin/1- cot = sin+cos...pls prove?

by  |  earlier

0 LIKES UnLike

Cos/1- tan + sin/1- cot = sin+cos...pls prove?

 Tags:

   Report

2 ANSWERS


  1. hi, could you please add on brackets? i.e. cos/(1- tan) + sin/(1- cot) = sin+cos

    or however it's supposed to be?

    ----------

    okay, I'm going to assume that the question is cos/(1- tan) + sin/(1- cot) = sin+cos and that it's standard sin/cos/tan theatas.

    cos/(1-(sin/cos)*) + sin/(1-(cos/tan)**) = sin + cos

    cos/(cos-sin)+ sin/(sin-cos) = sin + 1 - sin***

    cos/(cos-sin) - sin/(cos - sin) = 1

    (cos - sin)/(cos-sin) = 1

    1=1

    therefore, cos/(1- tan) + sin/(1- cot) = sin+cos


  2. LS = (cosx)/(1-tanx)+(sinx)/(1-cotx)

              change tanx to sinx/cosx, cotx to cosx/sinx

         = (cosx)/(1-(sinx/cosx))+(sinx)/(1-(cosx/s...

          multiply the first term by cosx/cosx, 2nd term by sinx/sinx (really multiplying both terms by 1

         = ((cosx)(cosx))/(cosx-sinx)+((sinx)(sinx)...

          multiply the first term by -1/-1 to get a common denominator

         = -((cosx)(cosx))/(sinx-cosx)+((sinx)(sinx...

         add the fractions

         = (sin^2x-cos^2x)/(sinx-cosx)

          use difference of squares to factor the numerator

         = ((sinx+cosx)(sinx-cosx))/(sinx-cosx)

           sinx-cosx in the numerator cancels with sinx-cosx in the denominator

         =sinx+cosx!

Question Stats

Latest activity: earlier.
This question has 2 answers.

BECOME A GUIDE

Share your knowledge and help people by answering questions.