Expand and simplify (3 + √ 2)(5 – √ 2)

To complete this question we can use the FOIL method.

First we can multiply out the First number in each of the brackets - 3x5=15

Then we multiply the Outer numbers in each bracket - 3x-√ 2=-3√ 2

Then the Inner numbers - √ 2x5=5√ 2

And finally the Last number in each bracket - √ 2x-√ 2=-2 as a square root times a square root is just the number.

We then add all our calculations - 15-3√ 2+5√ 2-2= 13+2√ 2

EJ
Answered by Emily J. Maths tutor

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