Question:

Express the given complex number in the form \(a + ib: (\dfrac{1}{3}+3i)^3\)

Updated On: Oct 18, 2023
Hide Solution
collegedunia
Verified By Collegedunia

Solution and Explanation

\((\dfrac{1}{3}+3i)^3\)

\(=(\dfrac{1}{3})^3+(3i)^{3}+3(\dfrac{1}{3}(3i)(\dfrac{1}{3}+3i))\)

\(=\dfrac{1}{27}-27i+i+9i^2\)

\(=\dfrac{1}{27}-27i+i-9\)

\(=\dfrac{-242}{27}-26i\) (Ans.)

Was this answer helpful?
0
0

Concepts Used:

Complex Numbers and Quadratic Equations

Complex Number: Any number that is formed as a+ib is called a complex number. For example: 9+3i,7+8i are complex numbers. Here i = -1. With this we can say that i² = 1. So, for every equation which does not have a real solution we can use i = -1.

Quadratic equation: A polynomial that has two roots or is of the degree 2 is called a quadratic equation. The general form of a quadratic equation is y=ax²+bx+c. Here a≠0, b and c are the real numbers.