Evaluate (78x+45y)2\Big(\dfrac{7}{8}x + \dfrac{4}{5}y\Big)^2(87x+54y)2
29 Likes
Solving,
⇒(78x+45y)2⇒(78x)2+(45y)2+2×78x×45y⇒4964x2+1625y2+75xy.\Rightarrow \Big(\dfrac{7}{8}x + \dfrac{4}{5}y\Big)^2 \\[1em] \Rightarrow \Big(\dfrac{7}{8}x\Big)^2 + \Big(\dfrac{4}{5}y\Big)^2 + 2 \times \dfrac{7}{8}x \times \dfrac{4}{5}y \\[1em] \Rightarrow \dfrac{49}{64}x^2 + \dfrac{16}{25}y^2 + \dfrac{7}{5}xy.⇒(87x+54y)2⇒(87x)2+(54y)2+2×87x×54y⇒6449x2+2516y2+57xy.
Hence, (78x+45y)2=4964x2+1625y2+75xy.\Big(\dfrac{7}{8}x + \dfrac{4}{5}y\Big)^2 = \dfrac{49}{64}x^2 + \dfrac{16}{25}y^2 + \dfrac{7}{5}xy.(87x+54y)2=6449x2+2516y2+57xy.
Answered By
19 Likes
If x2+1x2=9x^2 + \dfrac{1}{x^2} = 9x2+x21=9, the value of x4+1x4+5x^4 + \dfrac{1}{x^4} + 5x4+x41+5 is :
78
86
84
81
If x2 - 3x + 1 = 0, the value of
x2+1x2+1x^2 + \dfrac{1}{x^2} + 1x2+x21+1 is :
8
10
5
109\dfrac{10}{9}910
Evaluate (2x7−7y4)2\Big(\dfrac{2x}{7} - \dfrac{7y}{4}\Big)^2(72x−47y)2
Evaluate (a2b+2ba)2−(a2b−2ba)2−4\Big(\dfrac{a}{2b} + \dfrac{2b}{a}\Big)^2 - \Big(\dfrac{a}{2b} - \dfrac{2b}{a}\Big)^2 - 4(2ba+a2b)2−(2ba−a2b)2−4
