Question

va rog cele incercuite e urgeeent sa fie facute vorect va rog dau coroana si 19 puncte

Answer 1

Se utilizeaza formula A^{2}  -B^{2} = (A-B)(A+B)

100 X^{2} -4(3X+1)^{2}  = (10X)^{2} -[2(3X+1)]^{2}]=
= [10X-2(3X+1)][10X+2(3X+1)] =(10X-6X-2)(10X+6X+2)=
= (4X-2)(16X+2)

(2X+5)^{2} -(X-1)^{2}  =[2X+5 -(X-1)][2X+5 +(X-1)]=(2X+5-X+1)(2X+5+X-1)=
= (X+6)(3X+4)

Answer 2

$i)100 {x}^{2} - 4 {(3x + 1)}^{2}$

$= 100 {x}^{2} - 4( 9 {x}^{2} + 6x + 1)$

$= 100 {x}^{2} - 36 {x}^{2} - 24x - 4$

$= 64 {x}^{2} - 24x - 4$

$= 4(16 {x}^{2} - 6x - 1)$

$j) {(2x + 5)}^{2} - {(x - 1)}^{2}$

$= 4 {x}^{2} + 20x + 25 - ( {x}^{2} - 2x + 1)$

$= 4 {x}^{2} + 20x + 25 - {x}^{2} + 2x - 1$

$= 3 {x}^{2} + 22x + 24$