(i)6.25×6.25−1.754.5=(6.25)2−(1.75)24.5 Using identity, a2−b2=(a−b)(a+b) a=6.25 and b =1.75 =(6.25−1.75)(6.25+1.75)4.5=4.5×84.5=8
(ii)198×198−102×10296 Using identity, a2−b2=(a−b)(a+b) Now, 1982−102296=(198−102)(198+102)96 =96×30096=300
Find the values of (i) (82)2−(18)2 (ii) (128)2−(72)2 (iii) 197×203 (iv) 198×198−102×10296 (v) (14.7×15.3) (vi) (8.63)2−(1.37)2