Question

What is the Cartesian form of `(2,(pi)/4)`?

Answer 1

If Cartesian or rectangular coordinate of a point be (x,y)
and its polar polar coordinate be `(r,theta)`

then `x=rcostheta and y= rsintheta`
here `r=2 and theta =pi/4`
`x= 2*cos(pi/4)=2*1/sqrt2=sqrt2`
`y= 2*sin(pi/4)=2*1/sqrt2=sqrt2`

So Cartesian coordinate=`(sqrt2,sqrt2)`