If tan2A=2tan2B+1 then the value of cos2A+sin2B.
We are given tan2A=2tan2B+1
We want to find cos2A+sin2B
We are given the value of tan2A.So, write the value of cos2A in terms of tanA
cos2A=1−tan2A1+tan2A
cos2A+sin2B=1−tan2A1+tan2A+sin2B
Substituting the value of tan2A
= 1−(2tan2B+1)1+2tan2B+1+sin2B
= −2tan2B2(1+tan2B+sin2B
= −2tan2Bsec2B+sin2B
= −sin2B+sin2B
= 0