Advertisements
Advertisements
प्रश्न
If a + b = 7 and ab = 10; find a - b.
Advertisements
उत्तर
a + b = 7 and ab = 10
⇒ a (7 − a) = 10
⇒ 7a − a2 = 10
⇒ a2 − 7a + 10 = 0
⇒ a2 − 5a − 2a + 10 = 0
⇒ a (a − 5) − 2(a − 5) = 0
⇒ (a − 2) (a − 5) = 0
⇒ a = 5, 2
⇒ b = 2, 5
When a = 5, b = 2
⇒ a − b = 3
When a = 2,b = 5
⇒ a − b = −3
APPEARS IN
संबंधित प्रश्न
Write the following cube in expanded form:
(2x + 1)3
Evaluate the following using identities:
(2x + y) (2x − y)
Write in the expanded form:
`(a + 2b + c)^2`
Find the cube of the following binomials expression :
\[\frac{3}{x} - \frac{2}{x^2}\]
If a1/3 + b1/3 + c1/3 = 0, then
Find the square of `(3a)/(2b) - (2b)/(3a)`.
If a + `1/a`= 6 and a ≠ 0 find :
(i) `a - 1/a (ii) a^2 - 1/a^2`
Use the direct method to evaluate :
(2a+3) (2a−3)
If a2 + b2 + c2 = 41 and a + b + c = 9; find ab + bc + ca.
Give possible expressions for the length and breadth of the rectangle whose area is given by 4a2 + 4a – 3.
