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Popular >

cos(30)*9

Solution

cos (3 0^{\circ}) \cdot 9

Solution

\frac{9 3}{2}

+1

Decimal Notation

7.79422 \dots

Solution steps

cos (3 0^{\circ}) \cdot 9

Use the following trivial identity:

cos (3 0^{\circ}) = \frac{3}{2}

cos (3 0^{\circ})

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}

= \frac{3}{2}

= \frac{3}{2} \cdot 9

Simplify

\frac{3}{2} \cdot 9 : \frac{9 3}{2}

\frac{3}{2} \cdot 9

Multiply fractions:

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

= \frac{3 \cdot 9}{2}

= \frac{9 3}{2}

Popular Examples

sqrt(1+cos^2(pi/8))

1 + cos^{2} (\frac{π}{8})

cot (- \frac{17 π}{3})

6*0.5235sin(480)

6 \cdot 0.5235 sin (48 0^{\circ})

\frac{3}{cos ( 6 5 ^{\circ} )}

cos (0.875)

Frequently Asked Questions (FAQ)

What is the value of cos(30)*9 ?
The value of cos(30)*9 is (9sqrt(3))/2