## Kazwaz Group Title If tan x =3/5 and x is greater than 180 degrees but smaller than 270 degrees. What is the exact value of sin x and cos x ? 6 months ago 6 months ago

1. Mertsj Group Title

That means the angle is in Quadrant III

2. Mertsj Group Title

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3. Mertsj Group Title

Find the hypotenuse then use the definitions of sin and cos. (Remember: sin and cos are both negative in Quadrant III)

4. Kazwaz Group Title

Sorry, can you go a bit further. Trying to help my daughter .

5. Mertsj Group Title

Would I be correct in assuming that you know the Pythagorean Theorem?

6. Kazwaz Group Title

Yes

7. Mertsj Group Title

Use it to find the hypotenuse in that right triangle.

8. Kazwaz Group Title

5.83

9. Mertsj Group Title

I believe your problem specifies "exact form"

10. Kazwaz Group Title

So I leave it as sq root 34. Then cos x is -5/sq root 34 and sin x is -3/sq root 34. Is that correct?

11. Mertsj Group Title

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12. Kazwaz Group Title

Sorry, why are you multiplying by sq rt 34, then dividing by 34 ?

13. Mertsj Group Title

It is not considered simple form to have a radical in the denominator.

14. Mertsj Group Title

$\frac{5}{\sqrt{34}}\times \frac{\sqrt{34}}{\sqrt{34}}=\frac{5\sqrt{34}}{34}$

15. Kazwaz Group Title

Thanks for that. You've Ben a great help.

16. Kazwaz Group Title

been

17. Mertsj Group Title

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