Advertisements
Advertisements
प्रश्न
Find the value of 4x2 + y2 + 25z2 + 4xy − 10yz − 20zx when x = 4, y = 3 and z = 2.
उत्तर
We have,
`4x^2 + y^2 + 25z^2 + 4xy - 10yz - 20zx`
`=> (2x)^2 + (y)^2 + (-5z)^2 + 2(2x)(y) + 2(y)(-5z) + 2(-5z)(2x)`
`=:> (2x + y - 5z)^2`
`=> [2[4] + 3 - 5(2)]^2` [∵ x = 4, y = 3 and z = 2]
`= [8 + 3 - 10]^2`
`=[1]^2`
= 1
`∴ 4x^2 + y^2 + 25z^2 + 4xy - 10yz - 20zx = 1`
APPEARS IN
संबंधित प्रश्न
Use suitable identity to find the following product:
(x + 4) (x + 10)
Simplify the following: 175 x 175 x 2 x 175 x 25 x 25 x 25
if `x + 1/x = 11`, find the value of `x^2 + 1/x^2`
Simplify the following products:
`(1/2a - 3b)(1/2a + 3b)(1/4a^2 + 9b^2)`
Simplify the following products:
`(2x^4 - 4x^2 + 1)(2x^4 - 4x^2 - 1)`
Write in the expanded form: (ab + bc + ca)2
If \[x - \frac{1}{x} = - 1\] find the value of \[x^2 + \frac{1}{x^2}\]
Find the cube of the following binomials expression :
\[4 - \frac{1}{3x}\]
If a + b = 10 and ab = 21, find the value of a3 + b3
If `x - 1/x = 3 + 2sqrt2`, find the value of `x^3 - 1/x^3`
Find the following product:
(4x − 5y) (16x2 + 20xy + 25y2)
If \[x^4 + \frac{1}{x^4} = 194,\] then \[x^3 + \frac{1}{x^3} =\]
If \[x - \frac{1}{x} = \frac{15}{4}\], then \[x + \frac{1}{x}\] =
Use the direct method to evaluate the following products :
(3x – 2y) (2x + y)
Expand the following:
(x - 3y - 2z)2
Evaluate, using (a + b)(a - b)= a2 - b2.
4.9 x 5.1
If m - n = 0.9 and mn = 0.36, find:
m + n
Simplify:
(4x + 5y)2 + (4x - 5y)2
The coefficient of x in the expansion of (x + 3)3 is ______.
Find the following product:
(x2 – 1)(x4 + x2 + 1)
