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Popular >

cos(-pi/9)

Solution

cos (- \frac{π}{9})

Solution

cos (\frac{π}{9})

+1

Decimal Notation

0.93969 \dots

Solution steps

cos (- \frac{π}{9})

Use the following property:

cos (- x) = cos (x)

cos (- \frac{π}{9}) = cos (\frac{π}{9})

= cos (\frac{π}{9})

Popular Examples

sec (1 3^{\circ})

(tan(60)+tan(45))/(1-tan(60)tan(45))

\frac{tan ( 6 0 ^{\circ} ) + tan ( 4 5 ^{\circ} )}{1 - tan ( 6 0 ^{\circ} ) tan ( 4 5 ^{\circ} )}

arctan (- \frac{5}{6})

arccos (cos (1))

sin(arcsin((sqrt(3))/2)+arccos(1))

sin (arcsin (\frac{3}{2}) + arccos (1))

Frequently Asked Questions (FAQ)

What is the value of cos(-pi/9) ?
The value of cos(-pi/9) is cos(pi/9)