若sinθ+sin2θ=1，则cos2θ+cos6θ+cos8θ的值等于_刷题宝

题干

若sinθ+sin²θ=1，则cos²θ+cos⁶θ+cos⁸θ的值等于（）

A：0

B：1

C：﹣1

D： $\frac{\sqrt{5} - 1}{2}$

上一题下一题 0.0难度选择题更新时间:2013-01-17 01:37:55

答案(点此获取答案解析）

B

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