Advertisements
Advertisements
प्रश्न
If `49x^2 - b = (7x + 1/2)(7x - 1/2)`, then the value of b is ______.
पर्याय
0
`1/sqrt(2)`
`1/4`
`1/2`
उत्तर
If `49x^2 - b = (7x + 1/2)(7x - 1/2)`, then the value of b is `underlinebb(1/4)`.
Explanation:
Given, `(49x^2 - b) = (7x + 1/2)(7x - 1/2)`
⇒ `[49x^2 - (sqrt(b))^2] = [(7x)^2 - (1/2)^2]` ...[Using identity, (a + b)(a – b) = a2 – b2]
⇒ `49x^2 - (sqrt(b))^2 = 49x^2 - (1/2)^2`
⇒ `-(sqrt(b))^2 = -(1/2)^2`
⇒ `(sqrt(b))^2 = (1/2)^2` ...[Multiplying both sides by –1]
∴ `b = 1/4`
APPEARS IN
संबंधित प्रश्न
Use suitable identity to find the following product:
`(y^2+3/2)(y^2-3/2)`
Factorise the following:
64m3 – 343n3
Simplify the following: 175 x 175 x 2 x 175 x 25 x 25 x 25
Write in the expanded form:
`(a + 2b + c)^2`
Simplify (a + b + c)2 + (a - b + c)2 + (a + b - c)2
Find the following product:
If x = 3 and y = − 1, find the values of the following using in identify:
(9y2 − 4x2) (81y4 +36x2y2 + 16x4)
If x = 3 and y = − 1, find the values of the following using in identify:
\[\left( \frac{x}{y} - \frac{y}{3} \right) \frac{x^2}{16} + \frac{xy}{12} + \frac{y^2}{9}\]
If \[x^2 + \frac{1}{x^2} = 102\], then \[x - \frac{1}{x}\] =
If \[x^3 + \frac{1}{x^3} = 110\], then \[x + \frac{1}{x} =\]
If a + b + c = 9 and ab + bc + ca = 23, then a2 + b2 + c2 =
If \[x^4 + \frac{1}{x^4} = 623\] then \[x + \frac{1}{x} =\]
Evaluate: (2a + 0.5) (7a − 0.3)
Evaluate: `(2"a"+1/"2a")(2"a"-1/"2a")`
Find the squares of the following:
9m - 2n
Simplify by using formula :
(1 + a) (1 - a) (1 + a2)
Simplify:
`("a" - 1/"a")^2 + ("a" + 1/"a")^2`
Expand the following:
(3a – 5b – c)2
If a + b + c = 5 and ab + bc + ca = 10, then prove that a3 + b3 + c3 – 3abc = – 25.