What is the trigonometric form of (12-2i) (122i)?

1 Answer
Mar 11, 2016

2sqrt37 [ cos(-0.165) + isin(-0.165) ]237[cos(0.165)+isin(0.165)]

Explanation:

Using the following formulae :

• r^2 = x^2 + y^2r2=x2+y2

• theta = tan^-1 (y/x)θ=tan1(yx)

here x = 12 and y = - 2

hence r^2 = 12^2 + (-2)^2 = 148 rArr r = sqrt148 = 2sqrt37r2=122+(2)2=148r=148=237

and theta = tan^-1(-2/12) ≈ -0.165" radians " θ=tan1(212)0.165 radians

rArr (12-2i) = 2sqrt37 [cos(-0.165) + isin(-0.165) ](122i)=237[cos(0.165)+isin(0.165)]