Question

What is (14-3i)(14+3i)

Answer 1

Answer: 205

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Work Shown:

`(14-3i)(14+3i)\\\\x(14+3i) \ ... \text{ let } x = 14-3i\\\\14(x)+3i(x)\\\\14(14-3i)+3i(14-3i) \ ... \text{ plug in } x = 14-3i\\\\196-42i+42i-9i^2\\\\196-9i^2\\\\196-9(-1)\\\\196+9\\\\205`

Recall that
`i = √(-1)` is the imaginary unit. Squaring both sides gets us
`i^2 = -1`

You can verify the answer using a tool like WolframAlpha.