simplify cos(180)-x

Solution

simplify

cos (18 0^{\circ}) - x

- 1 - x

Solution steps

cos (18 0^{\circ}) - x

Use the following trivial identity:

cos (18 0^{\circ}) = (- 1)

cos (x)

periodicity table with

36 0^{\circ} n

cycle:

x 0 3 0^{\circ} 4 5^{\circ} 6 0^{\circ} 9 0^{\circ} 12 0^{\circ} 13 5^{\circ} 15 0^{\circ} cos (x) 1 \frac{3}{2} \frac{2}{2} \frac{1}{2} 0 - \frac{1}{2} - \frac{2}{2} - \frac{3}{2} x 18 0^{\circ} 21 0^{\circ} 22 5^{\circ} 24 0^{\circ} 27 0^{\circ} 30 0^{\circ} 31 5^{\circ} 33 0^{\circ} cos (x) - 1 - \frac{3}{2} - \frac{2}{2} - \frac{1}{2} 0 \frac{1}{2} \frac{2}{2} \frac{3}{2}

= - 1 - x

x^{4} + 4 x^{3} + 4 x^{2} - y^{2}

\frac{( - 13 x + 15 x ^{2} - 20 )}{( 3 x - 5 )}

(4 i^{w} \cdot k^{- 3 - n}) (- j \cdot k^{n + 3})

512 x^{3} + 27 y^{3}

(n^{3})^{7}