Question

98(sin²27°-cos²27°) / cos54°
по возможности побыстрее, пожалуйста)​

Answer 1

$\frac{98(Sin^{2}27^{o}-Cos^{2}27^{o})}{Cos54^{o}}=\frac{98*(-Cos54^{o})}{Cos54^{o} }=-98$

Answer 2

$\displaystyle \tt \frac{98\cdot\bigg(sin(27^{\circ})^2-cos(27^{\circ})^2\bigg)}{cos(54^{\circ})}=\frac{98\cdot\bigg(-cos(54^{\circ})\bigg)}{cos(54^{\circ})}=98\cdot(-1)=\underline{\bold{-98}}$