Given v = (4,9)
a. What is the angle between the vector and the x-axis?

b. Write the vector in polar form

Question

Given v = (4,9) 
a. What is the angle between the vector and the x-axis?

b. Write the vector in polar form

amistre64 · Answer

whats its tangent inverse?

amistre64 · Answer

|dw:1431211702496:dw|

amistre64 · Answer

polar form: (length,angle)

you know the angle, whats its length?

anonymous · Answer

$$\sqrt{4^{2}+9^{2}}$$ = $$\sqrt{97}$$ is what I have

anonymous · Answer

The length based on that triangle you drew, using the Pythagorean theorem would make the length equal to 97, right?

anonymous · Answer

sqt rt of 97 *

anonymous · Answer

so the length would be 9.848857802

amistre64 · Answer

sqrt 97 is a good length, dunno how 'simplified' it is but its valid to me

anonymous · Answer

so I have the length, I need the angle now. How could I set that up?

amistre64 · Answer

already posted it .... 

tan(angle) = 9/4

take the inverse ...

anonymous · Answer

66.03751103

amistre64 · Answer

even if we do a dot product equivalence, we still have to do an inverse so might as well work it from the start lol

amistre64 · Answer

yeah, about 66 degrees

amistre64 · Answer

exactness is:

(sqrt(97), arctan(9/4))

rnd them to whatever you like if need be

anonymous · Answer

(9.849, 66.038) yeah I need to do it in at least the thousandths place

amistre64 · Answer

:)  ok

anonymous · Answer

So now that I have the length and angle, how can i set that up in polar formation?

anonymous · Answer

wait, is that in polar form already? (9.849, 66.038)? @amistre64