Question

(3х+4)(3х-4)
(0,5b-6c) (0,5b+6c)
(7x²-y)(y+7x²)
(4m³+6n)(6n-4m³)
7(n²-2)-4(3+n)(n-3)
срочно пожалуйста

Answer 1

1) (3x+4)(3x-4)=(3x)^2-4^2=9x^2-16

2) (0,5b-6c)(0,5b+6c)=0,5^2×b^2-36c^2=0,25b^2-36c^2

3) (7x^2-y)(y+7x^2)=(7x^2-y)(7x^2+y)=49x^4-y^2

4) (4m^3+6n)(6n-4m^3)=(6n+4m^3)(6n-4m^3)=36n^2-16m^6

5) 7(n^2-2)-4(3+n)(n-3)=7n^2-14-4(n+3)(n-3)=7n^2-14-4(n^2-9)=7n^2-14-4n^2+36=3n^2+22