(1)3x=+/-(π/2-x)+2kπ,故x=+/- π/4+kπ(k∈Z)
(2)sin^2x+cos^2x=1=2sinxcosx+sinx-cosx
即(sinx-cosx)^2=sinx-cosx
則sinx-cosx=0或1,若sinx-cosx=0則x=+/-(π/2-x)+2kπ,x=π/4+kπ(k∈Z),
若sinx-cosx=1,即√2sin(x-π/4)=1 ,則x-π/4=π/4+kπ,x=π/2+kπ(k∈Z)
故x=π/4+kπ或π/2+kπ(k∈Z)
滿意請(qǐng)點(diǎn)“選為滿意答案”,祝你學(xué)習(xí)進(jìn)步!