11-1

This week we learned section 1 in chapter 11. 11-1 is really easy and quite simple. You will have to know formulas such as polar and rectangular.

To convert to rectangular you do x=rcostheta, y=rsintheta.


To convert to polar you do r=square roots of xsquared+ysquared and after you do tantheta=y/x then you find the inverse of it.

(r,theta)=polar, (x,y)=rectangular


Example Problems:

Give the Polar coordinates for the point (3,4)

R=square root 3squared+4squared=

R square root of 25 which is equal to +-5

Tantheta=4/3=

Theta=tan inverse of 4/3 you get 53.130degrees.

Where tan is + is 1st quadrant and 3rd quadrant which u do 180+53.130 =233.130degrees

Your answers are 5, 53.130degrees and -5,233.130degrees

Convert 2, 30 degrees to rectangular
X=2cos30 degrees which you get 2(square root of 3 over 2 because 30 degrees is on the trig chart you get square root of 3 as you answer.

Y=2sin30 degrees
Sin 30degrees is on the trig chart =to ½
2(1/2 you get 1

Your answers are squared root of 3 and 1.

If you know to convert to polar and rectangular and know every formula in 11-1 this section should be a joke for you.