davidwangxiang
幼苗
共回答了16个问题采纳率:93.8% 举报
紧跟题意 1、f(x)=a*b=-cos^2x+sinx*根 号3*cosx=sin(2x-π/6)-1/2
2、T=2π/2=π,-π/2+2kπ《2x-π/6《π/2+2kπ ,解得 kπ-π/6《x《π/3+kπ
3、闭区间0《x《π内,容易知道,[0,π/3]和【5π/6,π】递增,而在【π/3,5π/6】递减
关键值
f(π/3)=1/2,
f(0)=-1
f(5π/6)=-3/2
f(π)=-1 所以x=π/3,有最大值;x=5π/6,有最小值
1年前
2