Answer
$8 + 2 \sqrt 15$
Work Step by Step
$( \sqrt 3 + \sqrt 5 ) ^{2}$
Use FOIL to simplify. FOIL: First (Multiply the first variables in the brackets), outside (Multiply the outer variables), Inside (Multiply the inside variables), Last (Multiply the last variables in the brackets).
$3 + \sqrt 3 \sqrt 5 + \sqrt 3 \sqrt 5 + 5$
We add the radicals together and the numbers together
$8 + 2 \sqrt 3 \sqrt 5$
We multiply 3 and 5 and bring them under the same radical
$8 + 2 \sqrt 3 \times 5$
$8 + 2 \sqrt 15$
