Advertisement Remove all ads

Without actually calculating the cubes, find the value of the following:- (28)^3 + (–15)^3 + (–13)^3 - Mathematics

Advertisement Remove all ads
Advertisement Remove all ads
Advertisement Remove all ads

Without actually calculating the cubes, find the value of the following:- (28)3 + (–15)3 + (–13)3

Advertisement Remove all ads

Solution

(28)3 + (–15)3 + (–13)3 

Let x = 28, y = −15, and z = −13

It can be observed that,

x + y + z = 28 + (−15) + (−13) = 28 − 28 = 0

It is known that if x + y + z = 0, then

x3 + y3 + z3 = 3xyz

∴ (28)3 + (–15)3 + (–13)3 = 3(28)(-15)(-13) = 16380

Concept: Algebraic Identities
  Is there an error in this question or solution?

APPEARS IN

NCERT Class 9 Maths
Chapter 2 Polynomials
Exercise 2.5 | Q 14.2 | Page 49

Video TutorialsVIEW ALL [1]

Advertisement Remove all ads
Share
Notifications

View all notifications


      Forgot password?
View in app×