

InterviewSolution
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Write the following squares of binomials as trinomials:(i) \((x+2)^2\)(ii) \((8x+3b)^2\)(iii) \((2m+1)^2\)(iv) \((9a+\frac{1}{6})^2\)(v) \((x+\frac{x^2}{2})^2\)(vi) \((\frac{x}{4}-\frac{y}{3})\)(vii) \((3x-\frac{1}{3x})^2\)(viii) \((\frac{x}{y}-\frac{y}{x})^2\)(ix) \((\frac{3a}{2}-\frac{5b}{4})^2\)(x) \((a^2b-bc^2)^2\)(xi) \((\frac{2a}{3b}+\frac{2b}{3a})^2\)(xii) \((x^2-ay)^2\) |
Answer» (i) \((x+2)^2\) x2 + 2 (x) (2) + 22 = x2 + 4x + 4 (ii) \((8x+3b)^2\) (8x)2 + 2 (8x) (3b) + (3b)2 = 16x2 + 48xb + 9b2 (iii) \((2m+1)^2\) (2m)2 + 2 (2m) (1) + 12 = 4m2 + 4m + 1 (iv) \((9a+\frac{1}{6})^2\) (9a)2 + 2 (9a) (\(\frac{1}{6}\)) + (\(\frac{1}{6}\))2 = 81a2 + 3a + \(\frac{1}{36}\) (v) \((x+\frac{x^2}{2})^2\) (x)2 + 2 (x) (\(\frac{x\times x}{2}\)) + (\(\frac{x\times x}{2}\))2 = x2 + x3 + \(\frac{1}{4}\)x4 (vi) \((\frac{x}{4}-\frac{y}{3})\) (\(\frac{x}{4}\))2 – 2 (\(\frac{x}{4}\)) (\(\frac{y}{3}\)) + (\(\frac{y}{3}\))2 = \(\frac{1}{16}\)x2 - \(\frac{xy}{6}\) + \(\frac{1}{9}\)y2 (vii) \((3x-\frac{1}{3x})^2\) (3x)2 – 2 (3x) (\(\frac{1}{3x}\)) + (\(\frac{1}{3x}\))2 = 9x2 – 2 + \(\frac{1}{9\times x\times x}\) (viii) \((\frac{x}{y}-\frac{y}{x})^2\) (\(\frac{x}{y}\))2 – 2 (\(\frac{x}{y}\)) (\(\frac{y}{x}\)) + (\(\frac{y}{x}\))2 = \(\frac{x\times x}{y\times y}\) - 2 + \(\frac{y\times y}{x\times x}\) (ix) \((\frac{3a}{2}-\frac{5b}{4})^2\) (\(\frac{3a}{2}\))2 – 2 (\(\frac{3a}{2}\)) (\(\frac{5b}{4}\)) + (\(\frac{5b}{4}\))2 = \(\frac{9}{4}\)a2 - \(\frac{15}{4}\)ab + \(\frac{25}{16}\)b (x) \((a^2b-bc^2)^2\) (a2b)2 – 2 (a2b) (bc2) + (bc2)2 = a4b2 – 2a2b2c2 + b2c4 (xi) \((\frac{2a}{3b}+\frac{2b}{3a})^2\) (\(\frac{2a}{3b}\))2 + 2 (\(\frac{2a}{3b}\)) (\(\frac{2b}{3a}\)) + (\(\frac{2b}{3a}\))2 = \(\frac{4\times a\times a}{9\times b\times b}\) + \(\frac{8}{9}\)a + \(\frac{4\times b\times b}{9\times a\times a}\) (xii) \((x^2-ay)^2\) (x2)2 – 2 (x2) (ay) + (ay)2 = x4 – 2x2ay + a2y2 |
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