Question

Descompuneți în factori diferențele de pătrate: a)x²-16; b) y²-49; c)4a²-1; d)25x²-y²; e)16x²-25; f)81x²-49y²; g)1,69a²-1,44b²; h)1-1,96x²y².

Answer 1

a) x² - 16 = (x + 4)(x - 4) ;

b) y² - 49 = (y + 7)(y - 7) ;

c) 4a² - 1 = (2a + 1)(2a - 1) ;

d) 25x² - y² = (5x + y)(5x - y) ;

e)16x² - 25 = (4x + 5)(4x - 5) ;

f) 81x² - 49y² = (9x + 7y)(9x - 7y) ;

g)1,69a² - 1,44b² = ( 1,3a + 1,2b)(1,3a - 1,2b) ;

h)1 - 1,96x²y². = (1 + 1,4xy)(1 - 1,4xy)