What is the value of cos(pi/6)cos(pi/6)-sin(pi/6)sin(pi/6) ?

The value of cos(pi/6)cos(pi/6)-sin(pi/6)sin(pi/6) is 1/2

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cos(pi/6)cos(pi/6)-sin(pi/6)sin(pi/6)

cos (\frac{π}{6}) cos (\frac{π}{6}) - sin (\frac{π}{6}) sin (\frac{π}{6})

\frac{1}{2}

Decimal Notation

0.5

Solution steps

cos (\frac{π}{6}) cos (\frac{π}{6}) - sin (\frac{π}{6}) sin (\frac{π}{6})

Use the following trivial identity:

cos (\frac{π}{6}) = \frac{3}{2}

cos (\frac{π}{6})

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{3}{2}

Use the following trivial identity:

sin (\frac{π}{6}) = \frac{1}{2}

sin (\frac{π}{6})

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{1}{2}

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

Simplify

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

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

\frac{3}{2} \cdot \frac{3}{2} = \frac{3}{4}

\frac{3}{2} \cdot \frac{3}{2}

Multiply fractions:

\frac{a}{b} \cdot \frac{c}{d} = \frac{a \cdot c}{b \cdot d}

= \frac{3 3}{2 \cdot 2}

33 = 3

33

Apply radical rule:

a a = a

33 = 3

= 3

= \frac{3}{2 \cdot 2}

Multiply the numbers:

2 \cdot 2 = 4

= \frac{3}{4}

\frac{1}{2} \cdot \frac{1}{2} = \frac{1}{4}

\frac{1}{2} \cdot \frac{1}{2}

Multiply fractions:

\frac{a}{b} \cdot \frac{c}{d} = \frac{a \cdot c}{b \cdot d}

= \frac{1 \cdot 1}{2 \cdot 2}

Multiply the numbers:

1 \cdot 1 = 1

= \frac{1}{2 \cdot 2}

Multiply the numbers:

2 \cdot 2 = 4

= \frac{1}{4}

= \frac{3}{4} - \frac{1}{4}

Apply rule

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

= \frac{3 - 1}{4}

Subtract the numbers:

3 - 1 = 2

= \frac{2}{4}

Cancel the common factor:

2

= \frac{1}{2}

= \frac{1}{2}

\frac{24 sin ( 2 2 ^{\circ} )}{sin ( 4 0 ^{\circ} )}

tan (72 0^{\circ})

arctan (\frac{7}{15})

arctan (\frac{5.7}{5.4})

20 sin (3 5^{\circ})

What is the value of cos(pi/6)cos(pi/6)-sin(pi/6)sin(pi/6) ?
The value of cos(pi/6)cos(pi/6)-sin(pi/6)sin(pi/6) is 1/2