Question

2.
1. If x = a2– bc, y = b2 – ca, z = c2 -
ab then what is the value of
ax+by+cz
(a+b+c)(x+y+z)
(b) 1
(a) 2
(d) 3
(C)4​

Answer 1

Answer:

Correct option is

C

Step-by-step explanation:

(a+b+c)(x+y+z)

=(a+b+c)[a

2

+b

2

+c

2

−bc−ca−ab]

=a

3

+b

3

+c

3

−3abc ...(i)

Now, ax+by+cz=a(a

2

−bc)+b(b

2

−ca)+c(c

2

−ab)

=a

3

+b

3

+c

3

−3abc ...(ii)

∴

(ii)

(i)

=1

The value of the given expression is 1.