Математика, хелп ми плиз!

Решите задачу:

$3 \times {125}^{ \frac{1}{3} } - 0.3 = 3 \times \sqrt[3]{125} - 0.3 = 3 \times 5 - 0.3 = 15 - 0.3 = 14.7$
$log_{11}(24.2) + log_{11}(5) = log_{11}(24.2 \times 5) = log_{11}(121 ) = 2$
${sin }^{2} \alpha - 4 {cos}^{2} \alpha = 1 - {cos}^{2} \alpha - 4 {cos}^{2} \alpha = 1 - 5 {cos}^{2} \alpha = 1 - 5 \times{ ( - 0.8) }^{2} = 1 - 3.2 = - 2.2$