y=sinx怎样变化成y=sinx+cosx
问题描述:
y=sinx怎样变化成y=sinx+cosx
答
y=sinx+cosx =√2(√2/2*sinx+√2/2cosx) =√2(sinxcosπ/4+cosxsinπ/4) =√2sin(x+π/4) 所以是把y=sinx向左移π/4 然后把纵坐标变成原来的√2倍即可
y=sinx怎样变化成y=sinx+cosx
y=sinx+cosx =√2(√2/2*sinx+√2/2cosx) =√2(sinxcosπ/4+cosxsinπ/4) =√2sin(x+π/4) 所以是把y=sinx向左移π/4 然后把纵坐标变成原来的√2倍即可