问题 : 3 sin^2 ( x ) - 3 sin ( x ) 将表达式因式分解 3sin(x)(sin(x)−1) 求值 3sin2(x)−3sin(x)重写表达式 3sin(x)sin(x)−3sin(x)解题方案 3sin(x)(sin(x)−1) 显示解题方案