If (4x-7)(2x+13), then which of the following must be true?
ক
x>9
খ
x13
গ
x>7
ঘ
none of these
সঠিক উত্তর: none of these
(4x7) < (2x + 13) ⇒ 4x7 + 7 < 2x + 13 + 7 ⇒ 4x - 2x < 2x + 20 – 2x ⇒ 2x < 20 ∴x 10