## Venomblast Group Title put this in polar form 5-12i one year ago one year ago

1. Venomblast Group Title

i got r=13

2. Venomblast Group Title

I do not want my answers in degree

3. Venomblast Group Title

basically what i need help is converting my answer to degree to rad in decimal

4. terenzreignz Group Title

5. Venomblast Group Title

292.61 degree.

6. terenzreignz Group Title

In that case, if you have it in degrees, to bring it to radians, simply multiply it by the factor $\huge \frac{\pi}{180^o}$

7. Venomblast Group Title

|dw:1367393591344:dw|

8. agent0smith Group Title

|dw:1367393361730:dw| for a number a+bi $\large r^2 = a^2 + b^2$ tan theta = $\large \tan \theta = \frac{ b }{a }$ To convert from degrees to radians $\Large \theta ^{r} = \theta ^{d} \times \frac{ \pi }{180}$ theta d means theta in degrees.

9. Venomblast Group Title

hey one more question. if 5 was negative would it still be $\tan \theta b/a$ or will the a be negative?

10. agent0smith Group Title

Like this? |dw:1367393943561:dw| $\tan \theta = \frac{ -12 }{-5 }$ which gives theta = 67.4 degrees or 1.18 radians... BUT as you can see, theta is in the third quadrant, so you need to add 180 degrees to 67.4 degrees, or add pi radians to 1.18 radians... giving 247.4 degrees or 4.31 radians. This is why drawing a diagram is helpful.

11. Venomblast Group Title

no what I am trying to say is, does it matter of a or b is positive or negative or do you just take the absolute value of 12 and 5 when figuring out tan theta

12. agent0smith Group Title

Oh, no, you use b and a exactly as they are, you can take the abs value, but that just means more work to find the actual angle.

13. agent0smith Group Title

Because tan is negative in the 2nd and fourth quadrants, so it's helpful to keep the negatives as they are: http://upload.wikimedia.org/wikipedia/commons/thumb/a/a7/All_Students_Take_Calculus.svg/220px-All_Students_Take_Calculus.svg.png

14. Venomblast Group Title

i tan is always positive if you take the abs of a and b

15. agent0smith Group Title

Eh? we don't want tan to always be positive... there's no need for that. Keeping the negatives can actually save you some work...