若f(x)满足2f(-sinx)+3f(sinx)=4sinxcosx(-90<=x<=90).“度”我就不写了
热心网友
x=sina=x12f(-x1)+3f(x1)=4x1(1-x1^2)^0.5-x=-sina=x22f(-x2)+3f(x2)=4x2(1-x2^2)^0.5so2f(-x)+3f(x)=4x(1-x^2)^0.5 (1)2f(x)+3f(-x)=-4x(1-x^2)^0.5 (2)(1)*3-(2)*25f(x)=20x(1-x^2)^0.5f(x)=4x(1-x^2)^0.5
热心网友
2f(-sinx)+3f(sinx)=4sinxcosx(-90<=x<=90).sinx=t2f(-t)+3f(t)=4tgenhao(1-tt) (1)2f(t)+3f(-t)=-4tgenhao(1-tt) (2)解得3(1)-2(2)5f(t)=4tgenhao(1-tt) f(x)=4xgenhao(1-xx) /5-1<=x<=1