Question 2 - Page 147 - Square of the Sum/Difference of Two Numbers - Chapter 6 Class 8 - We Distribute yet things Multiply (Ganita Prakash)

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Question 2 - Page 147 Use the identity (a – b)2 to find the values of (a) 992 and (b) 582.For 〖𝟗𝟗〗^𝟐 It will be easier if we break it into 99 = 100 – 1 Now, 〖𝟗𝟗〗^𝟐=(𝟏𝟎𝟎−𝟏)^𝟐 =100^2−2 × 100 × 1+1^2 =10,000−200+1 =𝟗𝟖𝟎𝟏 For 〖𝟓𝟖〗^𝟐 It will be easier if we break it into 58 = 60 – 2 Now, 〖𝟓𝟖〗^𝟐=(𝟔𝟎−𝟐)^𝟐 =60^2−2 × 60 × 2+2^2 =3,600−240+4 =𝟑𝟑𝟔𝟒