# Math Help - Polar coordinates?

1. ## Polar coordinates?

Find the distance between these two polar points
P1(1.3,-47 degrees) and P2(-3.6,-62 degrees)

I know the formula to find distance is

square root R1^2+R2^2-2(R1R2)cos(angle 2- angle1)

But when I plug in the numbers in my calculator I get an unreal answer but checking the answer on the back of my math book I know that is incorrect.

Can anyone show me how to do this problem?

2. ## Answer

I get 2.74578
Is that the answer that you think it should be?

When you type it in:

is your -3.6 in () when you square it?

(1.3)^2 + (-3.6)^2 -2(1.3)(-3.6)Cos(-47 - -62) all under the radical sign.

also is your calculator in the correct mode if you can change it?