Advertisements
Advertisements
प्रश्न
If a + b + c = 9 and ab + bc + ca = 40, find a2 + b2 +c2.
Advertisements
उत्तर
Recall the formula
`(a+b+c)^2 = a^2 +b^2 +c^2 +2(ab +bc+ca)`
Given that
`(a+b+c) = 9,ab + bc + ca = 40`,
Then we have
`(a+b+c)^2 = a^2 + b^2 + c^2 + 2(ab + bc + ca)`
` ( 9)^2 = a^2 + b^2 + c^2 + 2.( 40) `
`a^2 ++ b^2 + c^2 + 80 = 81`
`a^2 + b^2 + c^2 = 81 - 80
`a^2 + b^2 +c^2 =` 1
APPEARS IN
संबंधित प्रश्न
Get the algebraic expression in the following case using variables, constants and arithmetic operations.
One-fourth of the product of numbers p and q.
Factorize a2 + 4b2 - 4ab - 4c2
Factorize the following expressions:
1029 – 3x3
Factorize the following expressions:
x3 + 6x2 +12x +16
Factorize a3 – 3a2b + 3ab2 – b3 + 8
`1/27 x^3 - y^3 + 125z^3 + 5xyz`
125 + 8x3 - 27 y3 + 90xy
What must be added to the following expression to make it a whole square?
4x2 − 20x + 20
In the given figure, the length of a green side is given by g and that of the red side is given by p.

Write an expression for the following pattern. Also write an expression if 100 such shapes are joined together.

Express the following properties with variables x, y and z.
Associative property of multiplication
