Question

2减cos平方10度分之3减sin70度的值为多少

Answer 1

(3-sin70°)/(2-cos²10°)

=(3-cos20°)/[2-(1+cos20°)/2]

=2(3-cos20°)/(4-1-cos20°)

=2(3-cos20°)/(3-cos20°)

=2