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If cos(t)=
-(4)/(9) evaluate cos(-t) and sec(-t)

User Marc Claesen
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1 Answer

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3 votes

Answer:

cos(-t) = -4/9

sec(-t) = -9/4

Step-by-step explanation:

Since cosine is an even function, we can say cos(-t) = cos(t) for all values of t. So this explains why cos(-t) = cos(t) = -4/9. No change happens.

To find the secant value, we apply the reciprocal. This is because sec = 1/cos. So that's how -4/9 flips to -9/4.

User Tarell
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