Using standard formulae, expand each of the following:

(i) $\Big(\dfrac{a}{2} + \dfrac{b}{3} + \dfrac{c}{4}\Big)^2$

(ii) $\Big(\dfrac{2x}{3} + \dfrac{3}{2y} - 2\Big)^2$

(iii) $\Big(2x + \dfrac{3}{x} - 1 \Big)^2$

Using standard formulae, expand each of the following:

(i) (x + 7)(x + 4)

(ii) (a + 13)(a - 8)

(iii) (y - 6)(y - 4)

Using standard formulae, expand each of the following:

(i) (3a + 2b)(3a - 2b)

(ii) $\Big(5x + \dfrac{1}{5x}\Big)\Big(5x - \dfrac{1}{5x}\Big)$

(iii) $\Big(2x^2 + \dfrac{3}{x^2}\Big)\Big(2x^2 - \dfrac{3}{x^2}\Big)$

Using standard formulae, expand each of the following:

(i) (2 - x)(2 + x)(4 + x²)

(ii) (x + y)(x - y)(x² + y²)