SSC CPO SI and ASI 2016 Paper

© examsiri.com

Question : 110 of 200

Marks: +1, -0

If p, q, r are all real numbers, then

(p – q)^3 + (q – r)^3 + (r – p)^3

is equal to

(p – q) (q – r) (r – p)
1
3 (p – q) (q – r) (r – p)
0

Solution:

(3)

a^{3}+b^{3}+c^{3}-3 a b c=(a+b+

c )(a^{2}+b^{2}+c^{2}-a b-b c-c a)

Here,

a=(p-q), b=(q-r), c=(r-

p )

a+b+c=p-q+q-r+r-p=0

Therefore,

(p-q)^{3}+(q-r)^{3}+(r-p)^{3}

=3(p-q)(q-r)(r-p)

© examsiri.com

Go to Question:

Prev Question

Next Question