nokia0816
幼苗
共回答了10个问题采纳率:90% 举报
2sin^a-cos^a+sina*cosa-6sina+3cosa=0
(2sina-cosa)(sina+cosa)-3(2sina-cosa)=0
(2sina-cosa)(sina+cosa-3)=0
(2sina-cosa)[√2(√2/2sina+√2/2cosa)-3]=0
(2sina-cosa)[√2(sinacosπ/4+cosasinaπ/4)-3]=0
(2sina-cosa)[√2sin(a+π/4)-3]=0
-1
1年前
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