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Popular >

-2cos(pi/4)

Solution

- 2 cos (\frac{π}{4})

Solution

- 2

+1

Solution steps

- 2 cos (\frac{π}{4})

Use the following trivial identity:

cos (\frac{π}{4}) = \frac{2}{2}

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

Simplify

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

= - 2

Popular Examples

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(tan(-(2pi)/3))/(sin((7pi)/4))-sec(-pi)

\frac{tan ( - \frac{2 π}{3} )}{sin ( \frac{7 π}{4} )} - sec (- π)

Frequently Asked Questions (FAQ)

What is the value of -2cos(pi/4) ?
The value of -2cos(pi/4) is -sqrt(2)