Question

помогите пж........... ​

Answer 1

Ответ:

Пошаговое объяснение:

1)

1) (x-4)^2=x^2-8x+16

2) (3a-7b)^2=9a^2-42ab+49b^2

3) (p-9)(p+9)=p^2-81

4) (2x+7y)(2x-7y)=4x^2-49y^2

2)

1) x^2-25=(x-5)(x+5)

2) a^2-14a+49=(a-7)^2

3) a^2+8a+16=(a+4)^2

4) 16y^2-36=4 (2y-3)(2y+3)

5) 81y^2-4x^2=(9y-2x)(9y+2x)

3)

1) (x-5)^2-x (x+3)=

=x^2-10x+25-x^2-3x=

= -13x+25

2) (6a-b)^2-(9a-b)(4a+2b)=

=36a^2-12ab+b^2-(36a^2-4ab+18ab-2b^2)=

= -12ab+4ab-18ab+b^2+2b^2=

= -26ab+3b^2

3) (x-2)^2+(x-1)(x+1)=

=x^2-4x+4+x^2-1=

=2x^2-4x+3

4) (3a-2b)(3a+2b)-(a+3b)^2=

=9a^2-4b^2-a^2-6ab-9b^2=

= 8a^2-6ab-13b^2

5) (y-4)(y+3)-(y+1)^2+(7-y)(7+y)=

=y^2-y-12-(y^2+2y+1)+49-y^2=

= -y^2-3y+36