How do you simplify $(8+sqrt(-18)) - (4+3sqrt(2) )$ ?

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Answer 1 · 2017-09-02T14:03:45

$4+3sqrt(2)(i-1)$

Before we start note that: $sqrt(-1)=i$

Write as: $8-4+sqrt((-1)xx(+18))-3sqrt2$

$4+sqrt(2xx3^2xx(-1))-3sqrt2$

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Using simple numbers to demonstrate a point

$sqrt16=sqrt(2^2xx2^2) =sqrt(2^2)xxsqrt(2^2)=4$

So you can 'split' the contents of a root.
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Using the above principle.

$4+3sqrt(2)sqrt(-1)-3sqrt(2)$

$4+3sqrt(2)(i-1)$

How do you simplify (8+sqrt(-18)) - (4+3sqrt(2) )(8+sqrt(-18)) - (4+3sqrt(2) )?