Advertisements
Advertisements
प्रश्न
If a + b = 10 and ab = 21, find the value of a3 + b3
Advertisements
उत्तर
In the given problem, we have to find the value of `a^3 + b^3`
Given `a+b = 10, ab = 21`
We shall use the identity `(a+b)^3 = a^3 +b^3 +3ab(a+b)`
Here putting, `a+b = 10,ab= 21`
`(10)^3 = a^3+ b^3 +3 (21)(10)`
` 1000 = a^3 +b^3 +630`
`1000 - 630 = a^3 +b^3`
`370 = a^3 + b^3`
Hence the value of `a^3 +b^3` is 370.
APPEARS IN
संबंधित प्रश्न
Use suitable identity to find the following product:
`(y^2+3/2)(y^2-3/2)`
Evaluate the following product without multiplying directly:
104 × 96
Factorise the following using appropriate identity:
9x2 + 6xy + y2
Write the following cube in expanded form:
(2x + 1)3
Give possible expression for the length and breadth of the following rectangle, in which their area is given:
| Area : 35y2 + 13y – 12 |
Simplify the following
`(7.83 + 7.83 - 1.17 xx 1.17)/6.66`
If 3x - 7y = 10 and xy = -1, find the value of `9x^2 + 49y^2`
Evaluate of the following:
463+343
Find the following product:
(4x − 3y + 2z) (16x2 + 9y2 + 4z2 + 12xy + 6yz − 8zx)
If \[x + \frac{1}{x} = 3\] then find the value of \[x^6 + \frac{1}{x^6}\].
If a + b + c = 0, then write the value of \[\frac{a^2}{bc} + \frac{b^2}{ca} + \frac{c^2}{ab}\]
If \[x^4 + \frac{1}{x^4} = 194,\] then \[x^3 + \frac{1}{x^3} =\]
The product (x2−1) (x4 + x2 + 1) is equal to
Use the direct method to evaluate :
(3x2+5y2) (3x2−5y2)
Evaluate: (4 − ab) (8 + ab)
If `"p" + (1)/"p" = 6`; find : `"p"^2 + (1)/"p"^2`
Evaluate the following :
1.81 x 1.81 - 1.81 x 2.19 + 2.19 x 2.19
Multiply x2 + 4y2 + z2 + 2xy + xz – 2yz by (–z + x – 2y).
