Answer:
![(√(17) )/(7)](https://img.qammunity.org/2020/formulas/mathematics/high-school/7u1y1tjm1zz25gu66lr7pn8fplvqbolwwn.png)
Explanation:
Given
cosΘ =
=
![(adjacent)/(hypotenuse)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/85syct3sa1xbi8qklwrzd1uiwes0nbmc54.png)
Then the hypotenuse of the right triangle is 7 and the adjacent side is 4
![√(2)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/t462m14cxkj26cw9cmocfpgj44y1v8li5n.png)
To find the opposite side use Pythagoras' identity
The square on the hypotenuse is equal to the sum of the squares on the other 2 sides, that is
opp² + (4
)² = 7²
opp² + 32 = 49 ( subtract 32 from both sides )
opp² = 17 ( take the square root of both sides )
opp =
![√(17)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/40do5mfc63vkkcpf0bosoncyas0gncdo96.png)
Hence
sinΘ =
=
![(√(17) )/(7)](https://img.qammunity.org/2020/formulas/mathematics/high-school/7u1y1tjm1zz25gu66lr7pn8fplvqbolwwn.png)