JAMB - Mathematics (2020 - No. 2)
Factorise (4a + 3) \(^2\) - (3a - 2)\(^2\)
(a + 1)(a + 5)
(a - 5)(7a - 1)
(a + 5)(7a + 1)
a(7a + 1)
설명
[(4a + 3) \(^2\) - (3a - 2)\(^2\) = a\(^2\) - b\(^2\) = (a + b) (a - b)
= [(4a + 3) + (3a - 2)] [(4a + 3) - (3a - 2)]
= [4a + 3 + 3a - 2] [4a + 3 - 3a + 2]
= (7a + 1)(a + 5)
(a + 5) (7a + 1)