write 2-2i in its modulus argument form

firsly sketch out the 2-2i on an argand diagrm and draw a line from (0,0) to (2,-2). With the shortest distance Mark the angle theta from the positive x-axis to the line to see whether the argument is positive or negative.

then do arctan(-2/2) to get the angle -pi/4. notice this angle is from the neative x-axis to the point (2,-2) so have to do pi-pi/4 to get the argument 3pi/4.

the to get the modulus it's sqrt(22+(-22)) which is root(8)

ZS

Related Further Mathematics A Level answers

All answers ▸

Express cos5x in terms of increasing powers of cosx


How far is the point (7,4,1) from the line that passes through the points (6,4,1) and (6,3,-1)?


z = 4 /(1+ i) Find, in the form a + i b where a, b belong to R, (a) z, (b) z^2. Given that z is a complex root of the quadratic equation x^2 + px + q = 0, where p and q are real integers, (c) find the value of p and the value of q.


Using the definitions of hyperbolic functions in terms of exponentials show that sech^2(x) = 1-tanh^2(x)