"If `acostheta+bsintheta=m` and `asintheta-bcostheta=n` , prove   that `a^2+b^2=m^2+n^2`"
Channel: Doubtnut
Date: 2020-06-28

"If `acostheta+bsintheta=m`
 and `asintheta-bcostheta=n`
 , prove
 
  that `a^2+b^2=m^2+n^2`"