What is the value of cos((2pi)/3)+sin((2pi)/3) ?

The value of cos((2pi)/3)+sin((2pi)/3) is (-1+sqrt(3))/2

English

Español

Português

Français

Deutsch

Italiano

Русский

中文(简体)

한국어

日本語

Tiếng Việt

עברית

العربية

Popular >

cos((2pi)/3)+sin((2pi)/3)

cos (\frac{2 π}{3}) + sin (\frac{2 π}{3})

\frac{- 1 + 3}{2}

Decimal Notation

0.36602 \dots

Solution steps

cos (\frac{2 π}{3}) + sin (\frac{2 π}{3})

Use the following trivial identity:

cos (\frac{2 π}{3}) = - \frac{1}{2}

cos (\frac{2 π}{3})

cos (x)

periodicity table with

2 πn

cycle:

x 0 \frac{π}{6} \frac{π}{4} \frac{π}{3} \frac{π}{2} \frac{2 π}{3} \frac{3 π}{4} \frac{5 π}{6} cos (x) 1 \frac{3}{2} \frac{2}{2} \frac{1}{2} 0 - \frac{1}{2} - \frac{2}{2} - \frac{3}{2} x π \frac{7 π}{6} \frac{5 π}{4} \frac{4 π}{3} \frac{3 π}{2} \frac{5 π}{3} \frac{7 π}{4} \frac{11 π}{6} cos (x) - 1 - \frac{3}{2} - \frac{2}{2} - \frac{1}{2} 0 \frac{1}{2} \frac{2}{2} \frac{3}{2}

= - \frac{1}{2}

Use the following trivial identity:

sin (\frac{2 π}{3}) = \frac{3}{2}

sin (\frac{2 π}{3})

sin (x)

periodicity table with

2 πn

cycle:

x 0 \frac{π}{6} \frac{π}{4} \frac{π}{3} \frac{π}{2} \frac{2 π}{3} \frac{3 π}{4} \frac{5 π}{6} sin (x) 0 \frac{1}{2} \frac{2}{2} \frac{3}{2} 1 \frac{3}{2} \frac{2}{2} \frac{1}{2} x π \frac{7 π}{6} \frac{5 π}{4} \frac{4 π}{3} \frac{3 π}{2} \frac{5 π}{3} \frac{7 π}{4} \frac{11 π}{6} sin (x) 0 - \frac{1}{2} - \frac{2}{2} - \frac{3}{2} - 1 - \frac{3}{2} - \frac{2}{2} - \frac{1}{2}

= \frac{3}{2}

= - \frac{1}{2} + \frac{3}{2}

Simplify

- \frac{1}{2} + \frac{3}{2} : \frac{- 1 + 3}{2}

- \frac{1}{2} + \frac{3}{2}

Apply rule

\frac{a}{c} \pm \frac{b}{c} = \frac{a \pm b}{c}

= \frac{- 1 + 3}{2}

= \frac{- 1 + 3}{2}

csc (- \frac{7 π}{3})

csc (6 π)

tan (\frac{25 π}{4})

e^{- 1} sin (1)

cos^{2} (4 5^{\circ}) + sin^{2} (4 5^{\circ})

What is the value of cos((2pi)/3)+sin((2pi)/3) ?
The value of cos((2pi)/3)+sin((2pi)/3) is (-1+sqrt(3))/2