Kąt α jest ostry i sinα= 2/3. Wtedy cos^2(90° -α) jest równy

$\displaystyle \frac{1}{9}$\displaystyle \frac{1}{9}

$\displaystyle \frac{2}{9}$\displaystyle \frac{2}{9}

$\displaystyle \frac{4}{9}$\displaystyle \frac{4}{9}

$\displaystyle \frac{5}{9}$\displaystyle \frac{5}{9}