Løs zeta-x^2=2cos15^circ

$$\zeta - x ^ { 2 } = 2 \cos 15 ^ { \circ }$$

Løs for ζ

$$\zeta =x^{2}+1,9318516525781366$$

Løsningstrinn

Evaluate trigonometric functions in the problem

$$\zeta - x ^ {2} = 2 \cdot 0,9659258262890683$$

Multipliser 2 med 0,9659258262890683 for å få 1,9318516525781366.

$$\zeta -x^{2}=1,9318516525781366$$

Legg til x^{2} på begge sider.

$$\zeta =1,9318516525781366+x^{2}$$

Løs for x

$$x=\frac{\sqrt{4\zeta -7,7274066103125464}}{2}$$

$$x=-\frac{\sqrt{4\zeta -7,7274066103125464}}{2}\text{, }\zeta \geq \frac{9659258262890683}{5000000000000000}$$