Question 5 (iii) - Algebra Identities and Formulas - Chapter 8 Class 8 Algebraic Expressions and Identities

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Ex 9.5, 5 - Chapter 9 Class 8 Algebraic Expressions and Identities - Part 3

Ex 9.5, 5 - Chapter 9 Class 8 Algebraic Expressions and Identities - Part 4

 

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Question 5 Show that. (iii) (4/3 𝑚−3/4 𝑛)^2+2𝑚𝑛=16/9 𝑚^2+9/16 𝑛^2 Solving LHS (4/3 𝑚−3/4 𝑛)^2+2𝑚𝑛 (𝑎−𝑏)^2=𝑎^2+𝑏^2−2𝑎𝑏 Putting 𝑎 = 4/3 𝑚 & 𝑏 = 3/4 𝑛 = (4/3 𝑚)^2+(3/4 𝑛)^2−2(4/3 𝑚)(3/4 𝑛)+2𝑚𝑛 = (4/3)^2×𝑚^2+(3/4)^2×𝑛^2−2𝑚𝑛+2𝑚𝑛 = 16/9 𝑚^2+9/16 𝑛^2 = RHS Since LHS = RHS Hence proved

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