if tanx =b/a , then what is the value of acos2x+bsin2x ? Share with your friends Share 3 Gursheen kaur. answered this Given: tanx =b/aacos2x+bsin2x 14 View Full Answer Ashish Jha answered this express cos2x and sin2x in terms of tanx.(use the formula) then substitute.....ans:- (a3 + ab2 ) / (a2+ b2 ) -3