Advertisements
Advertisements
Question
Expand `("x"-2/"x")^2`
Advertisements
Solution
It is known that (a + b)2 = a2 + 2ab + b2 and (a − b)2 = a2 − 2ab + b2.
`("x"-2/"x")^2`
= `("x")^2-2xx("x")xx(2/"x")+(2/"x")^2`
= `"x"^2-4+4/"x"^2`
RELATED QUESTIONS
Expand (2)2p − 3q
Factors of 4 – m2 are
The factors of x2 – 4x + 4 are __________
Expand the following square, using suitable identities
(xyz – 1)2
Show that (m – n)2 + (m + n)2 = 2(m2 + n2)
Using suitable identities, evaluate the following.
(9.9)2
Factorise the following, using the identity a2 – 2ab + b2 = (a – b)2.
`x^2/4 - 2x + 4`
Factorise the following.
y2 + 4y – 21
The curved surface area of a cylinder is 2π(y2 – 7y + 12) and its radius is (y – 3). Find the height of the cylinder (C.S.A. of cylinder = 2πrh).
Subtract b(b2 + b – 7) + 5 from 3b2 – 8 and find the value of expression obtained for b = – 3.
