Falling Behind in Studies? Join Our Performance Improvement Batch. Enroll For Free
One of our academic counsellors will contact you within 1 working day.
Click to Chat
1800-1023-196
+91-120-4616500
CART 0
Use Coupon: CART20 and get 20% off on all online Study Material
Welcome User
OR
LOGIN
Complete Your Registration (Step 2 of 2 )
If a – b = 3 and b – c = 5, then the value of a2 + b2 + c2 – ab – bc – ca is ?
A - b = 3 and b - c = 5 then a²+b²+c² - ab - bc - ca= ?a-b= 3⇒ a= 3+b ··· (1)b-c =5 ⇒ b= 5+c ···(2)From (1) and (2) we get, a = 3+5+c = 8+c •••(3)Now, a + b + c - ab - bc - ca = (8+c)²+(5+c)²+c² -(8+c)(5+c) - (5+c)(c) -(c)(8+c)=(64 + 16c +c²) + (25 + 10c + c²) + c² -(40+8c+5c+c²) - (5c+c²) - (8c+c²)=(64+25+ 26c + 3c²) - (40+26c+3c²)=(89 - 40)+ (26c -26c) + (3c² - 3c²)=89 - 40 =49
Post Question
Dear , Preparing for entrance exams? Register yourself for the free demo class from askiitians.
points won -