Question

If sin y° = 9 divided by c and tan y° = 9 divided by d, what is the value of cos y°?

Answer 1

siny=9/c

tany=9/d


we know that tany =siny/cosy==> 9/d=(9/c)/cosy

cosy=9d/c divided by 9 , that means multiply by 1/9

so cosy d/c

Answer 2

value of
`\cos y^(\circ)` is
`(d)/(c)`

Explanation:

Given :
`\sin y^(\circ)=(9)/(c) \\\\ \tan y^(\circ)=(9)/(d)`

we have to find the value of
`\cos y^(\circ)`

Using trigonometric relation between tangent , sine and cosine we have,

`\tan \theta=(\sin \theta)/(\cos \theta)`

We are given

`\sin y^(\circ)=(9)/(c) \\\\ \tan y^(\circ)=(9)/(d)`

Substitute, in relation above, we have

`\tan y^(\circ) =(\sin y^(\circ))/(\cos y^(\circ))`

`(9)/(d)=((9)/(c) )/(\cos y^(\circ))`

solve for
`\cos y^(\circ)` , we have

`\cos y^(\circ)=(9)/(c)* (d)/(9)`

Simplify , we get

`\cos y^(\circ)=(d)/(c)`

Thus, value of
`\cos y^(\circ)` is
`(d)/(c)`