已知f(x)=ax^2+bcosx+sinx-1满足f(π/6)=5,则f(-π/6)等于多少
问题描述:
已知f(x)=ax^2+bcosx+sinx-1满足f(π/6)=5,则f(-π/6)等于多少
答
f(-x)=ax^2+bcosx-sinx-1
f(x)=ax^2+bcosx+sinx-1
f(x)-f(-x)=2sinx
f(π/6)-f(-π/6)=2sin(π/6)=1
f(-π/6)=4