Chapter 9.9, Problem 8PSA

a

To determine

To find:The value of $\sin \angle RET$

Answer to Problem 8PSA

The value of $\sin \angle RET=\frac{12}{13}$

Explanation of Solution

Given information:The following information has been given

  $ET=26$

  $RT=24$

Formula used:Basic trigonometric identities have been used

Calculation:We apply the sine formula in the triangle RET, we get

  $\sin \angle RET=\frac{RT}{ET}$

Hence, we get

  $\sin \angle RET=\frac{12}{13}$

b

To determine

To find:The value of $\cos \angle RET$

Answer to Problem 8PSA

The value of $\cos \angle RET=\frac{5}{13}$

Explanation of Solution

Given information:The following information has been given

  $ET=26$

  $RT=24$

Formula used:Pythagoras theorem has been used in right triangle RET

Calculation:We apply the Pythagoras Theorem in right triangle RET , and we get

  ${24}^2+R{E}^2={26}^2$

Hence, we get

  $RE=10$

Now, we apply the cosine formula in the triangle RET, we get

  $\cos \angle RET=\frac{RE}{ET}$

Hence, we get

  $\cos \angle RET=\frac{5}{13}$