Advertisements
Advertisements
प्रश्न
Expand the following, using suitable identity:
(3a – 7b – c)2
Advertisements
उत्तर
It is known that,
(x + y + z)2 = x2 + y2 + z2 + 2xy + 2yz + 2zx
(3a – 7b – c)2 = (3a)2 + (–7b)2 + (–c)2 + 2(3a)(–7b) + 2(–7b)(–c) + 2(–c)(3a)
= 9a2 + 49b2 + c2 – 42ab + 14bc – 6ac
APPEARS IN
संबंधित प्रश्न
Evaluate the following using suitable identity:
(99)3
Factorise the following:
8a3 + b3 + 12a2b + 6ab2
What are the possible expressions for the dimensions of the cuboids whose volume is given below?
| Volume : 3x2 – 12x |
Simplify the following products:
`(1/2a - 3b)(1/2a + 3b)(1/4a^2 + 9b^2)`
Prove that a2 + b2 + c2 − ab − bc − ca is always non-negative for all values of a, b and c
Write in the expanded form: (ab + bc + ca)2
If \[x - \frac{1}{x} = 5\], find the value of \[x^3 - \frac{1}{x^3}\]
If 2x+3y = 13 and xy = 6, find the value of 8x3 + 27y3
Evaluate of the following:
(9.9)3
Evaluate of the following:
1113 − 893
If a + b = 7 and ab = 12, find the value of a2 + b2
(a − b)3 + (b − c)3 + (c − a)3 =
The product (x2−1) (x4 + x2 + 1) is equal to
If a2 - 3a + 1 = 0, and a ≠ 0; find:
- `a + 1/a`
- `a^2 + 1/a^2`
Use the direct method to evaluate the following products :
(3x – 2y) (2x + y)
If `x + (1)/x = 3`; find `x^4 + (1)/x^4`
If a2 + b2 + c2 = 41 and a + b + c = 9; find ab + bc + ca.
Simplify:
(x + y - z)2 + (x - y + z)2
Expand the following:
(3a – 2b)3
Expand the following:
`(4 - 1/(3x))^3`
