2sin50+cos10(1+根号3tan10)/根号2cos5

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2sin50+cos10(1+根号3tan10)/根号2cos5

2sin50+cos10(1+根号3tan10)/根号2cos5
2sin50+cos10(1+根号3tan10)/根号2cos5

2sin50+cos10(1+根号3tan10)/根号2cos5
哥算了半个多小时了.看好了.
=2sin50°+cos10°+(根号3)sin10°/根号下2cos5°
=2(sin50°+1/2cos10°+根号3/2sin10°)/根号下2cos5°
=2【sin50°+sin(30°+10°)】/根号下2cos5°
=2(sin50°+sin40°)/根号下2cos5°
关键公式:sin50°+sin40°=2sin【(50°+40)/2】乘以cos【(50°-40°)/2】
=4sin45°cos5°/根号2cos5°
=2
大大给点分,费了好多脑细胞

[2sin50°+cos10°(1+根号3tan10°)]/根号2cos5°
=[2sin50°+2sin(30°+10°)]/√2cos5°
=2sin45°cos5°/√2cos5°
=1

=2sin50+(cos10+根号3sin10)/根号2cos50
=2sin50+根号2sin40/cos50
=2sin50+根号2