<p>运算方法有以下两种:</p> <p>1.(sin²x)' = 2sinx(sinx)' = 2sinxcosx = sin2x。</p> <p>2.(sin²x)' = [(1-cos2x)/2]' = [1/2 - (cos2x)/2]' = 0 - ½(-sin2x)(2x)' = ½(sin2x)×2 = sin2x。</p> <p>拓展资料:<br></p> <p>设函数y=f(x)在点x0的某个邻域内有定义,当自变量x在x0处有增量Δx,(x0+Δx)也在该邻域内时,相应地函数取得增量Δy=f(x0+Δx)-f(x0);如果Δy与Δx之比当Δx→0时极限存在,则称函数y=f(x)在点x0处可导,并称这个极限为函数y=f(x)在点x0处的导数。</p> <p><a href="https://baike.baidu.com/item/%E5%AF%BC%E6%95%B0" target="_blank" title="百度百科_导数" rel="nofollow noopener">百度百科_导数</a><br></p>