a + b = 7 এবং ab = 10 হলে (a – b) = কত?
সমাধান
সঠিক উত্তর: Option B
আমরা জানি,
(a – b)2 = (a + b)2 - 4ab
= 72-4.10 = 49 - 40 = 9
⇒ (a – b)2 = 33
⇒ a – b= 3
(a – b)2 = (a + b)2 - 4ab
= 72-4.10 = 49 - 40 = 9
⇒ (a – b)2 = 33
⇒ a – b= 3
