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Given Triangle ABC where A and B are complementary angles. What is the equivalent to cos 25?

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Answer:

0.9063

Explanation:

Complementary angles are two angles whose sum is 90 degrees. In triangle ABC, if angle A and angle B are complementary, then we can write:

angle A + angle B = 90 degrees

Since this is a right triangle, we can use the trigonometric functions to find the lengths of the sides. The cosine of an angle is defined as the ratio of the adjacent side to the hypotenuse:

cos A = adjacent/hypotenuse

cos B = adjacent/hypotenuse

Since angles A and B are complementary, we can substitute 90 - A for B:

cos (90 - A) = adjacent/hypotenuse

sin A = adjacent/hypotenuse

So, to find the value of cos 25 degrees in this triangle, we need to find the sine of the complementary angle 65 degrees. Using the same logic as above, we can write:

sin (90 - 25) = adjacent/hypotenuse

cos 25 = adjacent/hypotenuse

We know that sin 65 = cos 25, so we can write:

cos 25 = sin 65

We can use a calculator to find that sin 65 is approximately 0.9063. Therefore, cos 25 is equivalent to approximately 0.9063.

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