ABC26GN0008 · Number System
Subject: General Aptitude · Chapter: Number System · Exam: · Marks: · Difficulty:
Simplify: (i) (387 × 387 + 113 × 113 + 2 × 387 × 113) (ii) (87 × 87 + 61 × 61 – 2 × 87 × 61)
Answer
Explanation
(i) Given Exp. = (387)2 + (113)2 + 2 × 387 × 113 = (a2 + b2 + 2ab), where a = 387 and b = 113 = (a + b)2 = (387 + 113)2 = (500)2 = 250000. (ii) Given Exp. = (87)2 + (61)2 – 2 × 87 × 61 = (a2 + b2 – 2ab), where a = 87 and b = 61 = (a – b)2 = (87 – 61)2 = (26)2 = (20 + 6)2 = (20)2 + 62 + 2 × 20 × 6 = (400 + 36 + 240) = (436 + 240) = 676.
Explanation as extracted from the printed page; notation may be imperfect.
Open in whiteboard · Browse this chapter in the app