(√3+√5)²

= (√3 + √5)(√3 + √5) {when squaring a binomial, multiply it by itself}

= √3 (√3) + √3 (√5) + √5 (√3) + √5 (√5) {used foil method}

= √9 + √15 + √15 + √25 {multiplied through}

= 3 + 2√15 + 5 {evaluated square roots}

=

**8 + 2√15**{combined like terms}

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