Advertisements
Advertisements
Question
If a+b=5 and ab = 6, find a2 + b2
Sum
Solution
(a + b)2 = a2 + b2 + 2ab
⇒ (5)2 = a2 + b2 + 2×6
⇒ 25 = a2 + b2 + 12
⇒ 25 − 12 = a2 + b2
⇒ 13 = a2 + b2
∴ a2 + b2 = 13
shaalaa.com
Application of Formulae
Is there an error in this question or solution?
APPEARS IN
RELATED QUESTIONS
If a – b = 6 and ab = 16, find a2 + b2
If `"a" + 1/"a"=3`, find `"a"^2+1/"a"^2`
If `"a" - 1/"a"=4`, find : `"a"^2+1/"a"^2`
If `"a"^2+ 1/"a"^2=23`, find : `"a" +1/"a"`
If a – b = 3 and ab = 10, find : a3 – b3.
Find : `"a"^3-1/"a"^3`, if `"a" -1/"a"=4`.
If `2"x"-1/(2"x")=4`, find : `8"x"^3-1/(8"x"^3)`
If a + b + c = 11 and a2 + b2 + c2 = 81, find : ab + bc + ca.
If 3x + 2y = 9 and xy = 3, find : 27x3 + 8y3.
The difference between the two numbers is 5 and their products are 14. Find the difference between their cubes.
