- #1
jboyd536
- 1
- 0
Calculate
( minus ( 2 over 3 ) + ( 2 over 3 ) i ) to the power minus 4,
simplifing your answer and giving it in the form a + i b, with a and b given exactly.I found the modulus by:
sqrt((-2/3)^2 + (2/3)^2)
= (2*sqrt(2))/3
the argument is:
pi - 1 (from a sketch in the complex plane)
hence:
-2/3 + 2/3i = (2*sqrt(2)/3)*(cos(pi-1)+isin(pi-1))
using de moivres formula:
(-2/3 + 2/3i)^4 = (2*sqrt(2)/3)^4*(cos(4(pi-1))+isin(4(pi-1)))
but what next? I know I need to convert to cartesian form but how?
( minus ( 2 over 3 ) + ( 2 over 3 ) i ) to the power minus 4,
simplifing your answer and giving it in the form a + i b, with a and b given exactly.I found the modulus by:
sqrt((-2/3)^2 + (2/3)^2)
= (2*sqrt(2))/3
the argument is:
pi - 1 (from a sketch in the complex plane)
hence:
-2/3 + 2/3i = (2*sqrt(2)/3)*(cos(pi-1)+isin(pi-1))
using de moivres formula:
(-2/3 + 2/3i)^4 = (2*sqrt(2)/3)^4*(cos(4(pi-1))+isin(4(pi-1)))
but what next? I know I need to convert to cartesian form but how?