Find the multiplicative inverse of 2−3i2-3 i.

Answer: The multiplicative inverse of 2−3i2-3i is 213+313i\frac{2}{13} + \frac{3}{13}i.

Step-by-step solution

Step 1: Define Multiplicative Inverse

The multiplicative inverse of a complex number zz is denoted as z−1z^{-1} or 1z\frac{1}{z}. For a complex number z=a+biz = a + bi, its multiplicative inverse is 1a+bi\frac{1}{a + bi}.

Step 2: Substitute the Complex Number

We are given the complex number z=2−3iz = 2-3i. We substitute this value into the formula for the multiplicative inverse.

Step 3: Multiply by the Conjugate

To simplify a complex fraction, we multiply both the numerator and the denominator by the conjugate of the denominator. The conjugate of 2−3i2-3i is 2+3i2+3i. This eliminates the imaginary part from the denominator.

Step 4: Perform Multiplication

Multiply the numerators and the denominators. In the denominator, we use the difference of squares formula, (a−b)(a+b)=a2−b2(a-b)(a+b) = a^2 - b^2.

Step 5: Simplify the Denominator

Recall that i2=−1i^2 = -1. Substitute this value into the denominator and simplify the expression.

Step 6: Express in Standard Form

Finally, express the result in the standard form of a complex number, a+bia+bi, by separating the real and imaginary parts.

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