Kąt α jest ostry i cosα= 3/4. Wtedy sinα jest równy

$\displaystyle \frac{1}{4}$\displaystyle \frac{1}{4}

$\displaystyle \frac{\sqrt{3}}{4}$\displaystyle \frac{\sqrt{3}}{4}

$\displaystyle \frac{\sqrt{7}}{4}$\displaystyle \frac{\sqrt{7}}{4}

$\displaystyle \frac{7}{16}$\displaystyle \frac{7}{16}