Let f(x) be a polynomial. Prove that if ∫01f(x)gn(x) dx=0 (n=0, 1, 2, ⋯), then all coefficients of f(x) are 0 for each case as follows.(1) gn(x)=(1+x)n(2) gn(x)=sinnπx(3) gn(x)=enx calculusintegrationtrigonometryalgebrapolynomialabsolute valuecalculus computations