当tan 2A 等于0.368则tan A 等于多少?

tan 2A 等于0.368,

第1个回答  2018-10-31
tan(2A)=2tanA/(1-tan²A)=0.368,
0.368tan²A+2tanA-0.368=0,
判别式△=2²-4×0.368×(-0.368)=4.541696≈2.131²,
tanA=(-2+2.131)/(2×0.368)≈0.178,
或tanA=(-2-2.131)/(2×0.368)≈-5.613本回答被网友采纳
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