Question

球数学三角函数的单调递增区间举个例子吧，及

Answer 1

比如说g(x)=sin[(1/2)x-π/8]
x属于[0,4π]则（1/2)x属于[0,2π]则(1/2)x-π/8属于[-π/8,15π/8]
如果设A=(1/2)x-π/8则题目转换成求sinA的单调增区间,A属于[-π/8,15π/8]
显然当A属于[-π/8,π/2]时sinA单调递增
显然当A属于[3π/2,15π/8]时sinA单调递增
把A换回成x
因为A=(1/2)x-π/8,所以A属于[-π/8,π/2]时则(1/2)x-π/8属于[-π/8,π/2]
则x属于[0,5π/4]
所以A属于[3π/2,15π/8]时则(1/2)x-π/8属于[3π/2,15π/8]
则x属于[13π/4,4π]
所以最后答案为x属于[0,5π/4]或x属于[13π/4,4π]