急!sin²1°+sin²2°+…………+sin²89°+sin²90°=
sin²1°+sin²2°+……sin²88°+sin²89°
sin²1°+sin²2°+sin²89°+sin²88°=
计算:sin²1°+sin²2°+sin²3°...+sin²45°+sin
数列求和 sin²1°+sin²2°+sin²3°+.+sin²88°+sin&
计算,tan91°tan92°……tan179°/sin²1°+sin²2°+……+sin²
证明sin(a+b)sin(a-b)=sin²a-sin² b,并用该式计算sin²20°
sin²40°+sin²50°+2-tan135°怎么算=
尽快 我今天将就要!化简(计算)1、Sin²10°+Sin²20°+Sin²30°+Sin
求sin²20°+sin80°sin40°,并且要用sin(α+β)sin(α-β)=sin²α-s
泰勒公式的为什么㏑( 1 + sin X ) = sin X - ( sin X )²/2 +(sin X )
sin^2 (0°)+sin^2( 1°)+.+sin^2(90du) 求和
√(cos 60°-1)²+2√cot 45°-sin 60°+|sin 30°-1|=?