2.1 Ungkapan Kuadratik (Contoh Soalan)
Contoh 1:
Bentukkan suatu ungkapan kuadratik dengan mendarab setiap yang berikut.
(a)
(6p – 2)(2p – 1)
(b)
(m + 5)(4 – 7m)
(c)
(x + 2) (2x – 3)
Penyelesaian:
(a)
(6p – 2)(2p – 1)
= (6p)(2p) + (6p)( –1) + (–2)(2p) + (–2)( –1)
= 12p2– 6p – 4p + 2
= 12p2– 10p + 2
(b)
(m + 5)(4 – 7m)
= (m)(4) + (m)(-7m) + (5)(4) + (5)(-7m)
= 4m – 7m2 + 20 – 35m
= –7m2– 31m + 20
(c)
(x + 2) (2x – 3)
= (x)(2x) + (x)( –3) + (2)(2x) + (2)( –3)
= 2x2– 3x + 4x – 6
= 2x2
+ x - 6