Questions: Use the figure below to find the exact value of the trigonometric function of angle A.
cot (A)
Transcript text: Use the figure below to find the exact value of the trigonometric function of angle $A$.
\[
\cot (A)
\]
Solution
Solution Steps
Step 1: Identify the sides of the right triangle
In the given right triangle, the lengths of the sides are:
Opposite side to angle A: 4
Adjacent side to angle A: 10
Hypotenuse: Not given directly
Step 2: Calculate the hypotenuse using the Pythagorean theorem
The Pythagorean theorem states that in a right triangle, the square of the hypotenuse (c) is equal to the sum of the squares of the other two sides (a and b):
\[ c^2 = a^2 + b^2 \]
\[ c^2 = 4^2 + 10^2 \]
\[ c^2 = 16 + 100 \]
\[ c^2 = 116 \]
\[ c = \sqrt{116} \]
\[ c = 2\sqrt{29} \]
Step 3: Calculate cotangent of angle A
The cotangent (cot) of an angle in a right triangle is the ratio of the length of the adjacent side to the length of the opposite side:
\[ \cot(A) = \frac{\text{adjacent}}{\text{opposite}} \]
\[ \cot(A) = \frac{10}{4} \]
\[ \cot(A) = \frac{5}{2} \]