If you remember that the square of i is –1, you can reduce these to purely real numbers before you even FOIL.
In a + bi form, 5 is just 5 + 0i, so a + b will be 5 + 0 = 5.
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(3i^2 + 2)(3i^2 -2) The expression shown above can be written as the complex number ai+b, where a and b are real numbers. What is the value of a+b? Thanks!!