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x是锐角,sinxcosx=2√3/7,则tanx=?
题目详情
x是锐角,sinxcosx=2√3/7,则tanx=?
▼优质解答
答案和解析
tgx=sinx/cosx=sinxcosx/cos^2x...(1)
sinxcosx=2√3/7
sin2x=2sinxcosx=4√3/7
cos2x=1/7=2cos^2x-1
cos^2x=(1/7+1)/2=4/7代入(1)
tgx=2√3/7÷4/7=√3/2
sinxcosx=2√3/7
sin2x=2sinxcosx=4√3/7
cos2x=1/7=2cos^2x-1
cos^2x=(1/7+1)/2=4/7代入(1)
tgx=2√3/7÷4/7=√3/2
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