asinx=bcosx=2ctanx1−tan2xand a2−b22=kc2a2+b2⇒k=
1
3
4
2
Take asinx=bcosx=ctan2x=lsay⇒sinx=la, cosx=lb, tan2x=lc Now 1=sin2x+cos2x=la2+lb2=l2a2+b2a2b2
=c2tan22xa2+b2a2b2 =c22tanx1-tan2x2a2+b2a2b2 =c22ba1-ba22a2+b2a2b2 ∵tanx=ba
⇒a2-b22=4c2a2+b2 ⇒k=4