f(x)=sinx+cosx =√2*(√2/2sinx+√2/2cosx) =√2*sin(x+π/4)所以f(x)的最小正周期租中耐为2π由于-1<=sin(x+π/4)<培慎=1所以-√2<=√2*sin(x+π/弊春4)<=√2即-√2<=f(x)<=√2所以f(x)的最大值为√2,最小值为-√2
根据公式,所亮洞碰以原式=跟好2SIN(X+4分之派)所以颤基周期为2最大跟好敬谈2 最小负跟好2
最小正周期是 2pi, 最大值根号2,最小值负根号2