SOLUTION: Express the complex numbers in standard form: (sqrt5-i*sqrt2)(sqrt5+i*sqrt2)

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Question 1155849: Express the complex numbers in standard form: (sqrt5-i*sqrt2)(sqrt5+i*sqrt2)
Answer by ikleyn(52754) About Me  (Show Source):
You can put this solution on YOUR website!
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Use the formula (identity)  (a+b)*(a-b) = a%5E2 - b%5E2.


It is valid for any numbers "a" and "b", including complex numbers.


In your case, a = sqrt%285%29,  b = sqrt%282%29.


Therefore, the answer is  %28sqrt%285%29%29%5E2 - %28-1%29%5E2%2A%28sqrt%282%29%29%5E2 = 5 + 2 = 7.


ANSWER.  (sqrt(5) - i*sqrt(2))*((sqrt(5) + i*sqrt(2)) = 7.

Solved.