Advertisements
Advertisements
प्रश्न
If x + y = 9, xy = 20
find: x2 - y2.
Advertisements
उत्तर
x + y = 9, xy = 20
We know (x - y) (x + y)
= x2 - y2
⇒ x2 - y2
= (±1) (9)
= ±9.
APPEARS IN
संबंधित प्रश्न
Verify:
x3 – y3 = (x – y) (x2 + xy + y2)
If 3x - 7y = 10 and xy = -1, find the value of `9x^2 + 49y^2`
Simplify the following products:
`(x/2 - 2/5)(2/5 - x/2) - x^2 + 2x`
Find the following product:
\[\left( \frac{3}{x} - \frac{5}{y} \right) \left( \frac{9}{x^2} + \frac{25}{y^2} + \frac{15}{xy} \right)\]
If x = 3 and y = − 1, find the values of the following using in identify:
(9y2 − 4x2) (81y4 +36x2y2 + 16x4)
If \[\frac{a}{b} + \frac{b}{a} = 1\] then a3 + b3 =
If p + q = 8 and p - q = 4, find:
pq
If `"r" - (1)/"r" = 4`; find: `"r"^2 + (1)/"r"^2`
Simplify:
`("a" - 1/"a")^2 + ("a" + 1/"a")^2`
Using suitable identity, evaluate the following:
101 × 102
