1a)xˇ2 -yˇ2 = (x+y)(x-y)
b)4aˇ2 - bˇ2 = (2a+b)(2a-b)
c)0,09aˇ2 -9bˇ2 = 9(0,01aˇ2 - bˇ2)=9.(0,1a+b)(0,1-b)
2a)144-25yˇ2 = (12+5y)(12-5y)
b)aˇ2bˇ2 - 4 = (ab+2)(ab-2)
c)4/9xˇ2 -1/16yˇ2 = (2/3x+1/4y)(2/3x - 1/4y)
3a)79ˇ2 -21ˇ2 = (79+21 )(79-21) = 100.58=5800
b)17,8ˇ2 - 7,8ˇ2 = (17,8+7,8)(17,8 -7,8)=25,6.10=256
1a)mˇ2 - nˇ2 = (m+n)(m-n)
b)9xˇ2 -yˇ2 = ( 3x+y)(3x-y)
c)49cˇ2 - 0,04aˇ2 = (7c+0,2a)(7c - 0,2a)
2a)121-36xˇ2 = (11+6x)(11-6x)
b)xˇ4yˇ4 - 9 = (xˇ2yˇ2+3)(xˇ2yˇ2 -3)
c)16/49aˇ2 - 1/9bˇ2 = (4/7a+1/3b)(4/7a - 1/3b)
3a)86ˇ2-14ˇ2 = (86+14)(86-14) = 100.72 = 7200
b)15,9ˇ2 -5,9ˇ2 = (15,9+5,9)(15,9-5,9)=21,8.10=218