1.y=sin(π/4-x)2.sin(x+π/4)3.cos(2x+π/4)取哪五点画图,最值及对应的X的值集合,单调区间求救,希望能遇到贵人相救,小弟先谢谢了

Question

1.y=sin(π/4-x) 2.sin(x+π/4) 3.cos(2x+π/4)取哪五点画图,最值及对应的X的值集合,单调区间
求救,希望能遇到贵人相救,小弟先谢谢了

Answer 1

1 (π/4,0)(3π/4,-1)(5π/4,0)(7π/4,1)(9π/4,0) ymax=1(x=2kπ+7π/4) ymin=-1(x=2kπ+3π/4) 单增区[2kπ+3π/4,2kπ+7π/4] 单减区[2kπ-π/4,2kπ+3π/4]2 (-π/4,0)(π/4,1)(3π/4,0)(5π/4,-1)(7π/4,0) yma...