Advertisements
Advertisements
Question
Expand the following, using suitable identity:
(–2x + 3y + 2z)2
Advertisements
Solution
It is known that,
(x + y + z)2 = x2 + y2 + z2 + 2xy + 2yz + 2zx
(–2x + 3y + 2z)2 = (–2x)2 + (3y)2 + (2z)2 + 2(–2x)(3y) + 2(3y)(2z) + 2(2z)(–2x)
= 4x2 + 9y2 + 4z2 – 12xy + 12yz – 8xz
APPEARS IN
RELATED QUESTIONS
Use suitable identity to find the following product:
(x + 8) (x – 10)
Factorise the following using appropriate identity:
`x^2 - y^2/100`
Expand the following, using suitable identity:
`[1/4a-1/2b+1]^2`
Without actually calculating the cubes, find the value of the following:
(–12)3 + (7)3 + (5)3
Evaluate following using identities:
991 ☓ 1009
If `x^2 + 1/x^2 = 66`, find the value of `x - 1/x`
Simplify the expression:
`(x + y + z)^2 + (x + y/2 + 2/3)^2 - (x/2 + y/3 + z/4)^2`
If 3x − 2y = 11 and xy = 12, find the value of 27x3 − 8y3
If x + y + z = 8 and xy +yz +zx = 20, find the value of x3 + y3 + z3 −3xyz
Evaluate : (4a +3b)2 - (4a - 3b)2 + 48ab.
If a + `1/a`= 6 and a ≠ 0 find :
(i) `a - 1/a (ii) a^2 - 1/a^2`
Evaluate: `(3"x"+1/2)(2"x"+1/3)`
Expand the following:
(x - 5) (x - 4)
Expand the following:
(3x + 4) (2x - 1)
If `"a" - 1/"a" = 10`; find `"a"^2 - 1/"a"^2`
If p + q = 8 and p - q = 4, find:
pq
If a2 - 3a - 1 = 0 and a ≠ 0, find : `"a" - (1)/"a"`
Evaluate the following :
7.16 x 7.16 + 2.16 x 7.16 + 2.16 x 2.16
Expand the following:
`(4 - 1/(3x))^3`
Find the following product:
`(x/2 + 2y)(x^2/4 - xy + 4y^2)`
