Question 293596
Hint: For any polar number in the form {{{z=r(cos(x)+i*sin(x))}}}, where 'r' is the magnitude and 'x' is the angle, it can be converted into rectangular form {{{a+bi}}} using the following equations:



1) {{{r=sqrt(a^2+b^2)}}} (this can be seen if you draw out a triangle with sides 'a', 'b', and hypotenuse 'r')


2) {{{tan(x)=b/a}}} (again this can be seen with a drawing of the triangle) Note: since 'b' is the vertical side, this is the side opposite from the angle 'x'



So in this case, {{{r=4}}} and {{{x=pi/4}}} meaning that {{{4=sqrt(a^2+b^2)}}} and {{{tan(pi/4)=b/a}}}. You'll then find that you'll have two equations and two unknowns which means that you can solve for both 'a' and 'b'.