y = sinx +2 求XY 是多少

y(x)=sin(x)+2, x,y=??Ans:-1<=sin(x)<=1 => -1+2<=sin(x)<=1+2=> 1<=y(x)<=3.....ansy=1, -1=sin(x) => x=-pi/2y=2, 0=sin(x) => x=0y=3, 1=sin(x) => x=pi/2所以 -pi/2<=x<=pi/2.....ans

嗯,如果題目只有這樣,那應該沒辦法算出XY之值,
頂多把 Y代入得 XY= x(sinx + 2)
不過題目應該不太可能這樣出,版主再確認一下題目是否有誤.

求XY相乘?
是不是少了什麼限制條件?