Övningsuppgift: Multiplicera Polynom

Du har räknat rätt, det är fel i facit.

Du har fått rätt svar.

Uppgiften är denna, och facit verkar alltid ha fel på den.

Tack för svaren!

Facit ger mig alltid fel svar på alla "Multiplicera polynom"  när utgångspunkten är två parenteser som ska multipliceras. 

Har dubbelkollat min multiplikation och finner inget fel.

Facits svar verkar konsekvent vara att

$(a+b)(c+d)=ac+a(d+1)+bc+bd$

Här är ett par att öva på...

(5x^11+3)(1-4x^12) = -20x^23-12x^12+5x^11+3

(5x^3+4)(3x^10-2) = 15x^13+12x^10-10x^3-8

(-2x^5-3)(-x^8-1) = 2x^13+3x^8+2x^5+3

(4x^8-2)(x^6-1) = 4x^14-4x^8-2x^6+2

(3x^4+3)(2-x^9) = -3x^13-3x^9+6x^4+6

(2x^3+1)(-5x^11-3) = -10x^14-5x^11-6x^3-3

(5x^6+2)(5x-1) = 25x^7-5x^6+10x-2

(5x^8+1)(1-4x^9) = -20x^17-4x^9+5x^8+1

(x^9+5)(-x^3-4) = -x^12-4x^9-5x^3-20

(3x^4-5)(4-2x^10) = -6x^14+10x^10+12x^4-20

(2-4x^4)(3-2x^4) = 8x^8-16x^4+6

(2x^5+1)(4x^2-2) = 8x^7-4x^5+4x^2-2

(2x^7-1)(-3x^6-1) = -6x^13-2x^7+3x^6+1

(4-5x^6)(4x^3-5) = -20x^9+25x^6+16x^3-20

(-2x^5-4)(5x^11+4) = -10x^16-20x^11-8x^5-16

(5-4x^11)(3x^9+4) = -12x^20-16x^11+15x^9+20

(1-4x^4)(2-2x) = 8x^5-8x^4-2x+2

(3-3x^8)(3x^5+4) = -9x^13-12x^8+9x^5+12

(5x^5-5)(x^12+5) = 5x^17-5x^12+25x^5-25

(-5x^6-5)(x^7-4) = -5x^13-5x^7+20x^6+20

(x^2+3)(3x^3+1) = 3x^5+9x^3+x^2+3

(x^12+1)(3x^6-4) = 3x^18-4x^12+3x^6-4

(2x^10-3)(2x^8+3) = 4x^18+6x^10-6x^8-9

(3-4x^4)(4x^5-5) = -16x^9+12x^5+20x^4-15

(5-4x^3)(2-5x^10) = 20x^13-25x^10-8x^3+10

(2x^8+1)(4x^2+2) = 8x^10+4x^8+4x^2+2

(-2x^8-1)(4-x^7) = 2x^15-8x^8+x^7-4

(2x^10+5)(4-5x^4) = -10x^14+8x^10-25x^4+20

(5-x)(3x^4+2) = -3x^5+15x^4-2x+10

(3x^3+4)(x^12+5) = 3x^15+4x^12+15x^3+20

(4x^5+4)(4-4x^7) = -16x^12-16x^7+16x^5+16

(x^11-3)(-5x^7-4) = -5x^18-4x^11+15x^7+12

(-4x^3-4)(5-3x^5) = 12x^8+12x^5-20x^3-20

(x^9+1)(2-2x^9) = 2-2x^18

(-2x^5-4)(-x^5-4) = 2x^10+12x^5+16

(x^6+3)(x^11-4) = x^17+3x^11-4x^6-12

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

(x^8-5)(-5x^12-5) = -5x^20+25x^12-5x^8+25

(5-4x^9)(2-5x) = 20x^10-8x^9-25x+10

(3-x^2)(5x^11+2) = -5x^13+15x^11-2x^2+6

(3x^11-3)(1-2x^12) = -6x^23+6x^12+3x^11-3

(-4x^9-1)(-3x^9-5) = 12x^18+23x^9+5

(5-3x^4)(x^3-5) = -3x^7+15x^4+5x^3-25

(4x^8+2)(2x^8+4) = 8x^16+20x^8+8

(5x^10-1)(2-5x^12) = -25x^22+5x^12+10x^10-2

(3x^4+1)(2-5x^2) = -15x^6+6x^4-5x^2+2

(x^9-2)(5x^9+1) = 5x^18-9x^9-2

(5x^4-4)(3-3x^4) = -15x^8+27x^4-12

(3x^6-4)(3x^9+1) = 9x^15-12x^9+3x^6-4

(5x-4)(5-x^9) = -5x^10+4x^9+25x-20

(-5x^7-4)(4x^8-1) = -20x^15-16x^8+5x^7+4

(4x^11-2)(2x^11-3) = 8x^22-16x^11+6

(4x^5-4)(5-3x^5) = -12x^10+32x^5-20

(3x+3)(5-3x) = -9x^2+6x+15

(4x^9+4)(4x^8-5) = 16x^17-20x^9+16x^8-20

(-5x^7-5)(2-3x^3) = 15x^10-10x^7+15x^3-10

(3x-2)(2x-1) = 6x^2-7x+2

(5x^9+5)(4x^8-2) = 20x^17-10x^9+20x^8-10

(5x^5-2)(5x^6+1) = 25x^11-10x^6+5x^5-2

(2x^9-3)(x^6-2) = 2x^15-4x^9-3x^6+6

(2-3x^11)(x^2-2) = -3x^13+6x^11+2x^2-4

(2x^7+2)(5-4x^11) = -8x^18-8x^11+10x^7+10

(x^5-2)(4-2x^7) = -2x^12+4x^7+4x^5-8

(1-3x^2)(5-5x^7) = 15x^9-5x^7-15x^2+5

(x^11+2)(5x^10+5) = 5x^21+5x^11+10x^10+10

(-x^10-5)(5x^7-2) = -5x^17+2x^10-25x^7+10

(3x^9-2)(-3x^3-1) = -9x^12-3x^9+6x^3+2

(-2x^6-2)(4x^11-4) = -8x^17-8x^11+8x^6+8

(1-4x^2)(4-x^10) = 4x^12-x^10-16x^2+4

(-2x^4-4)(-2x^9-4) = 4x^13+8x^9+8x^4+16

(2-x^6)(3x^12+2) = -3x^18+6x^12-2x^6+4

(2-2x^5)(3x^11-3) = -6x^16+6x^11+6x^5-6

(3x^11-4)(5x^5-5) = 15x^16-15x^11-20x^5+20

(x^5-3)(2-3x^8) = -3x^13+9x^8+2x^5-6

(3x^5+4)(-2x^4-4) = -6x^9-12x^5-8x^4-16

(4-5x^11)(3x^2+4) = -15x^13-20x^11+12x^2+16

(3x^3+4)(1-5x^9) = -15x^12-20x^9+3x^3+4

(5-5x^12)(3x^3+4) = -15x^15-20x^12+15x^3+20

(3x^7+1)(5-4x^8) = -12x^15-4x^8+15x^7+5

(5-4x)(1-2x^7) = 8x^8-10x^7-4x+5

(-x^3-1)(2x-5) = -2x^4+5x^3-2x+5

(3-2x^3)(2x^4-4) = -4x^7+6x^4+8x^3-12

(-x-2)(x^8+3) = -x^9-2x^8-3x-6

(2x^6-3)(4-2x^7) = -4x^13+6x^7+8x^6-12

(x^8-3)(5x-1) = 5x^9-x^8-15x+3

(5x^4+4)(5x^7+1) = 25x^11+20x^7+5x^4+4

(-5x-1)(3x^11+2) = -15x^12-3x^11-10x-2

(4-4x^11)(3-5x^8) = 20x^19-12x^11-20x^8+12

(5x^5-5)(2x^6+5) = 10x^11-10x^6+25x^5-25

(1-3x^10)(x^12-2) = -3x^22+x^12+6x^10-2

(2-2x^10)(1-4x^3) = 8x^13-2x^10-8x^3+2

(3x^6-3)(x^8-2) = 3x^14-3x^8-6x^6+6

(-5x^3-2)(-3x^3-1) = 15x^6+11x^3+2

(2x^4-5)(5-4x^6) = -8x^10+20x^6+10x^4-25

(-4x-2)(-5x^4-3) = 20x^5+10x^4+12x+6

(3x^6-3)(4x^8-4) = 12x^14-12x^8-12x^6+12

(4x^9+2)(4x+1) = 16x^10+4x^9+8x+2

(x^7-3)(3-x^2) = -x^9+3x^7+3x^2-9

(5-4x^6)(-2x^5-5) = 8x^11+20x^6-10x^5-25

(2x^3-5)(4x^2-5) = 8x^5-10x^3-20x^2+25

Jag har informerat Mattecentrum om problemet.

Tack för svaren, jag ska fortsätta med att öka svårighetsgraden på övningsuppgifterna och vara medveten om att facit kan ha fel.