必修四数学
创始人
2025-07-20 00:11:52
0次
必修四数学
sin50°(1+√3tan10°)
=sin50°((cos10°+√3sin10°)/cos10°)
=2sin50°(1/2cos10°+√3/2sin10°)/cos10°
=2sin50°(sin30°cos10°+cos30°sin10°)/cos10°
=2sin50°(sin(30°+10°))/cos10°
=2sin50°sin40°/cos10°
=2cos40°sin40°/cos10°
=sin80°/cos10°
=cos10°/cos10°=1
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