Evaluate: (2"A"+1/"2a")(2"A"-1/"2a")

Evaluate: `(2"a"+1/"2a")(2"a"-1/"2a")`

Sum

`(2"a"+1/"2a")(2"a"-1/"2a")`

`=(2"a")^2-(1/"2a")^2` ......[ ∵ (a − b) (a + b) = a²b²]

`=4"a"^2-1/"4a"^2`

shaalaa.com

Is there an error in this question or solution?

Chapter 12: Identities - Exercise 12 (D) [Page 155]

Chapter 12 Identities
Exercise 12 (D) | Q 2.04 | Page 155

Evaluate following using identities:

(a - 0.1) (a + 0.1)

Write in the expand form: `(2x - y + z)^2`

Simplify the following expressions:

`(x + y - 2z)^2 - x^2 - y^2 - 3z^2 +4xy`

Find the value of 64x³ − 125z³, if 4x − 5z = 16 and xz = 12.

\[\frac{( a^2 - b^2 )^3 + ( b^2 - c^2 )^3 + ( c^2 - a^2 )^3}{(a - b )^3 + (b - c )^3 + (c - a )^3} =\]

Find the square of 2a + b.

Use the direct method to evaluate :
(2a+3) (2a−3)

Evaluate: (4 − ab) (8 + ab)

Find the squares of the following:
9m - 2n

If `"a" + 1/"a" = 6;`find `"a" - 1/"a"`