Question

1) (4а²-6ab+1)-(3ab-4a²)
2) -5a(a⁴-6a²+3)
3) (x+4)(3x-2)
4) (6m+5n)(7m-3n)
5) (7x²-4x+8)+(4x²-x-5)​

Answer 1

1) (4а²-6ab+1)-(3ab-4a²) = 4а²- 6аb +1-3ab+4a² = 8a²- 9ab+1

2) -5a(a⁴-6a²+3) = -5a× a⁴-5a×(-6a²)-5a×3= -5a⁵+ 30a³ - 15a

3) (x+4)(3x-2) = x×3x-2x+4×3x-4×2 = 3x²-2x+12x-8 = 3x²+10x-8

4) (6m+5n)(7m-3n) = 6m×7m-6m×3n+5n×7m-5n×3n = 42m²-18mn+35mn-15n² = 42m²+ 17mn- 15n²

5) (7x²-4x+8)+(4x²-x-5) = 7x²-4x+8+4x²-x-5 = 11x²- 5x+3