How do you simplify $(1+sqrt7i)(-2-sqrt5i)$ ?

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Answer 1 · 2018-07-07T14:35:57

$-2+sqrt(35)-(2sqrt(7)+sqrt(5))i$

We are Using that $i^2=-1$
so we get by expanding

$-2-2sqrt(7)i-sqrt(5)i+sqrt(35)$
this equal to

$-2+sqrt(35)-(2sqrt(7)+sqrt(5))i$

How do you simplify (1+sqrt7i)(-2-sqrt5i)(1+sqrt7i)(-2-sqrt5i)?