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Popular >

simplify cos(pi+kpi)

Solution

simplify

cos (π + kπ)

Solution

- (- 1)^{k}

Solution steps

cos (π + kπ)

Rewrite using trig identities

= - cos (πk)

Use the basic trigonometric identity:

cos (nπ) = (- 1)^{n}

= - (- 1)^{k}

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Frequently Asked Questions (FAQ)

What is cos(pi+kpi) ?
The solution to cos(pi+kpi) is -(-1)^k