已知函数f(x)=f'(π/4)cos+sinx,则f(π/4)=?
问题描述:
已知函数f(x)=f'(π/4)cos+sinx,则f(π/4)=?
答
f'(x)=-f'(π/4)sinx+cosx.f'(π/4)=-f'(π/4)(1/2)^2+(1/2)^2.解得f'(π/4)=根号2-1
已知函数f(x)=f'(π/4)cos+sinx,则f(π/4)=?
f'(x)=-f'(π/4)sinx+cosx.f'(π/4)=-f'(π/4)(1/2)^2+(1/2)^2.解得f'(π/4)=根号2-1