Evaluate (2x+5)2−(2x−5)2
Given (2x+5)2−(2x−5)2Since, we have a2−b2=(a−b)(a+b)Substitute a=2x+5 and b=2x−5, we get (2x+5)2−(2x−5)2=(2x+5−(2x−5))(2x+5+2x−5)=(2x+5−2x+5)(2x+2x)=10(4x)=40xTherefore, the value of given expression is 40x.
Question 4(ii) Simplify: (2x+5)2−(2x−5)2