Q.

Ifπ/6π/31-sin2xdx=α+β2+γ3, where α,β, and γ are rational numbers, then 3α+4β-γ is equal to ¯____.       [2024]


Ans.

(6)

Let I=π/6π/31-sin2xdx

=π/6π/3(sinx-cosx)2dxI=π/6π/3|sinx-cosx|dx

=π/6π/4(cosx-sinx)dx+π/4π/3(sinx-cosx)dx

=[sinx+cosx]π/6π/4+[-cosx-sinx]π/4π/3

=(12+12-12-32)+(-12-32+12+12)

=42-1-3=-1+22-3

So, α=-1,β=2,γ=-1

  3α+4β-γ=-3+8+1=6