Question

Can you please answer this

Answer 1

Answer:

sorry I don't know answer

Step-by-step explanation:

please mark as brainliest

Answer 2

Answer:

Given:

x = (√5 + √3) / (√3 - √2)

y = (√5 - √3) / (√3 + √2)

Solution:

3x² + 8xy + 3y² (LHS) = a + b√10 (RHS)

LHS:

3x² + 8xy + 3y²

=⟩ 3 × [(√5 + √3) / (√3 - √2)]² + 8 × [(√5 + √3) / (√3 - √2)] × [(√5 - √3) / (√3 + √2)] + 3 × [(√5 - √3) / (√3 + √2)]²

=⟩ 3 × (√5 + √3)² / (√3 - √2)² + 8 × [(√5 + √3) / (√3 - √2)] × [(√5 - √3) / (√3 + √2)] + 3 × (√5 - √3)² / (√3 + √2)²

=⟩ 3 × [(5 + 3 + 2√15) / (3 + 2 - 2√6)] + 8 × [(5 - 3) / (3 - 2)] + 3 × [(5 + 3 - 2√15) / (3 + 2 + 2√6)]

=⟩ 3 × [(8 + 2√5) / (5 - 2√6)] + 8 × (2 / 1) + 3 × [(8 - 2√5) / (5 + 2√6)]

=⟩ [(24 + 6√15) / (5 - 2√6)] + 8 + [(24 - 6√15) / (5 + 2√6)]

=⟩ (120 + 48√6 + 30√15 + 12√90 + 120 - 48√6 - 30√15 + 12√90 + 8) / 1

=⟩ 240 + 24√90 + 8

=⟩ 240 + 24√(9 × 10) + 8

=⟩ 240 + 72√10 + 8

=⟩ 248 + 72√10

RHS:

a + b√10

LHS = RHS

=⟩ 248 + 72√10 = a + b√10

Therefore, a = 248 and b = 72

Hence, a + b = 248 + 72 = 320 (Ans)

(I guess your book is Foundation Mathematics, and some of its options in the MCQ section are wrong, but let me know if my answer is wrong. Anyways, even if my answer is wrong, my process is right which will help you. Cheers ;)