Advertisements
Advertisements
Question
If a2 - 3a - 1 = 0 and a ≠ 0, find : `"a"^2 - (1)/"a"^2`
Sum
Advertisements
Solution
`"a"^2 - (1)/"a"^2`
= `("a" + 1/"a")("a" - 1/"a")`
= `(±sqrt(13)) (3)`
= ±3`sqrt(13)`.
shaalaa.com
Is there an error in this question or solution?
APPEARS IN
RELATED QUESTIONS
Factorise the following:
64a3 – 27b3 – 144a2b + 108ab2
Evaluate following using identities:
991 ☓ 1009
Find the following product:
\[\left( \frac{2}{x} + 3x \right) \left( \frac{4}{x^2} + 9 x^2 - 6 \right)\]
If \[\frac{a}{b} + \frac{b}{a} = 1\] then a3 + b3 =
If a - b = 4 and a + b = 6; find
(i) a2 + b2
(ii) ab
The difference between two positive numbers is 5 and the sum of their squares is 73. Find the product of these numbers.
If x + y = 9, xy = 20
find: x - y
If `x + (1)/x = 3`; find `x^4 + (1)/x^4`
If p2 + q2 + r2 = 82 and pq + qr + pr = 18; find p + q + r.
Expand the following:
`(4 - 1/(3x))^3`
