Use the Direct Method to Evaluate : ("A"/2-"B"/3)("A"/2+"B"/3)

Use the direct method to evaluate :
`("a"/2-"b"/3)("a"/2+"b"/3)`

Sum

Note: (a+b) (a−b) = a² − b²

`("a"/2-"b"/3)("a"/2+"b"/3)`

`=("a"/2)^2-("b"/3)^2`

`="a"^2/4-"b"^2/9`

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Chapter 12 Identities
Exercise 12 (A) | Q 2.12 | Page 150

Factorise the following using appropriate identity:

9x² + 6xy + y²

Evaluate the following using identities:

`(a^2b - b^2a)^2`

If a + b + c = 9 and ab + bc + ca = 23, find the value of a² + b² + c².

Find the following product:

\[\left( 3 + \frac{5}{x} \right) \left( 9 - \frac{15}{x} + \frac{25}{x^2} \right)\]

Use identities to evaluate : (97)²

If a² - 5a - 1 = 0 and a ≠ 0 ; find:

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

Evaluate: (2 − z) (15 − z)

Expand the following:
(a + 4) (a + 7)

Evaluate the following without multiplying:
(95)²