Given $\cos t=\frac{4 \sqrt{5}}{9}$, evaluate the indicated functions. Write your answer as a simplified fraction, if necessary.
Part: 0 / 3
Part 1 of 3
(a) $\cos (-t)=\square$

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Answer

Final Answer: $\boxed{\frac{4 \sqrt{5}}{9}}$

Steps

Step 1 ：To find the value of $\cos (-t)$, we need to remember that the cosine function is an even function, which means that $\cos (-t) = \cos (t)$.

Step 2 ：Since we are given that $\cos t=\frac{4 \sqrt{5}}{9}$, we can directly use this value for $\cos (-t)$.

Step 3 ：$\cos (-t) = \frac{4 \sqrt{5}}{9}$

Step 4 ：Final Answer: $\boxed{\frac{4 \sqrt{5}}{9}}$