Advertisements
Advertisements
Question
If a + b = 10 and ab = 18, find the value of a2 + b2
Sum
Solution
We have (a + b)2 = a2 + 2ab + b2
(a + b)2 = a2 + b2 + 2ab
given a + b = 0 and ab = 18
102 = a2 + b2 + 2(18)
100 = a2 + b2 + 36
100 – 36 = a2 + b2
a2 + b2 = 64
shaalaa.com
Is there an error in this question or solution?
APPEARS IN
RELATED QUESTIONS
Use a suitable identity to get the following products.
`(3a - 1/2)(3a - 1/2)`
Use a suitable identity to get the following products.
(a2 + b2) (− a2 + b2)
Simplify (2.5p − 1.5q)2 − (1.5p − 2.5q)2
Using identities, evaluate (5.2)2
Expand (ax + by)2
Of which of the binomials given below is m2n2 + 14mnpq + 49p2q2 the expansion?
Use the formula to multiply the following.
(3x − 5) (3x + 5)
Use a formula to multiply of (2a – 13)(2a + 13)
Factorise the following, using the identity a2 + 2ab + b2 = (a + b)2.
4x4 + 12x3 + 9x2
The area of a rectangle is x2 + 7x + 12. If its breadth is (x + 3), then find its length.
