((x-5)(x+5)-(x-2)^3-7x^2+(x+1)(x^2-x+1)=(x+3)^3-(x^3+9x^2)\), \((x-4)^3-(x-5)(x^2+5x+25)=(x-2)(x^2-2x+4)-(x+4)^3-(x-7)\), \((x+1)^3-(x+3)(x^2-3x+9)=(x-3)^3+3(2x+1)^2-(x^3-5x+1)\)

các bạn giúp mình làm hết với nha.
Mình cảm ơn
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12) \((x-5)(x+5)-(x-2)^3-7x^2+(x+1)(x^2-x+1)=(x+3)^3-(x^3+9x^2)\)

13) \((x-4)^3-(x-5)(x^2+5x+25)=(x-2)(x^2-2x+4)-(x+4)^3-(x-7)\)

14) \((x+1)^3-(x+3)(x^2-3x+9)=(x-3)^3+3(2x+1)^2-(x^3-5x+1)\)

15) \(- (x+5)(x^2-5x+25)+(x+3)^3=(x-3)^2-(x-2)^3-(6x^2-x^3)\)

16) \((x-6)(x^2+6x+36)-(x+4)^3=(x-2)^3+(x+5)(x^2-10x+25)-(2x^3-6x^2)\)

17) \((2x+3)(4x^2-6x+9)-(2x-1)^3=(x+4)^3-(x-2)(x^2+2x+4)\)