Question 4 - Mind the Mistake, Mend the Mistake - Chapter 6 Class 8 - We Distribute yet things Multiply (Ganita Prakash)

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Question 4 We have expanded and simplified some algebraic expressions below to their simplest forms. (i) Check each of the simplifications and see if there is a mistake. (ii) If there is a mistake, try to explain what could have gone wrong. (iii) Then write the correct expression.Is there a mistake? Yes What went wrong? This is a very common mistake! The student thought (a + b)2 is just a2 + b2. It is not. You are missing the middle term. Remember the identity: (a + b)2 = a2 + 2ab + b2 Correct solution (5m+6n)^2 =(𝟓𝒎)^𝟐+𝟐 × 𝟓𝒎 × 𝟔𝒏+(𝟔𝒏)^𝟐 =5^2 × 𝑚^2+2 × 5 × 6 × 𝑚 × 𝑛+6^2 × 𝑛^2 =𝟐𝟓𝐦^𝟐+𝟔𝟎𝒎𝒏+𝟑𝟔𝒏^𝟐