Løs y=8-x+1/2(x-4)(2x-1/4x^2+1)-2(2-2x+1/4x^2-1)

$$y = 8 - x + \frac { 1 } { 2 } ( x - 4 ) ( 2 x - \frac { 1 } { 4 } x ^ { 2 } + 1 ) - 2 ( 2 - 2 x + \frac { 1 } { 4 } x ^ { 2 } - 1 )$$

Løs for y

$$y=-\frac{\left(x-8\right)\left(x^{2}+4\right)}{8}$$

Løsningsvejledning

Brug fordelingsegenskaben til at multiplicere \frac{1}{2} med x-4.

$$y=8-x+\left(\frac{1}{2}x-2\right)\left(2x-\frac{1}{4}x^{2}+1\right)-2\left(2-2x+\frac{1}{4}x^{2}-1\right)$$

Brug fordelingsegenskaben til at multiplicere \frac{1}{2}x-2 med 2x-\frac{1}{4}x^{2}+1, og kombiner ens led.

$$y=8-x+\frac{3}{2}x^{2}-\frac{1}{8}x^{3}-\frac{7}{2}x-2-2\left(2-2x+\frac{1}{4}x^{2}-1\right)$$

Kombiner -x og -\frac{7}{2}x for at få -\frac{9}{2}x.

$$y=8-\frac{9}{2}x+\frac{3}{2}x^{2}-\frac{1}{8}x^{3}-2-2\left(2-2x+\frac{1}{4}x^{2}-1\right)$$

Subtraher 2 fra 8 for at få 6.

$$y=6-\frac{9}{2}x+\frac{3}{2}x^{2}-\frac{1}{8}x^{3}-2\left(2-2x+\frac{1}{4}x^{2}-1\right)$$

Subtraher 1 fra 2 for at få 1.

$$y=6-\frac{9}{2}x+\frac{3}{2}x^{2}-\frac{1}{8}x^{3}-2\left(1-2x+\frac{1}{4}x^{2}\right)$$

Brug fordelingsegenskaben til at multiplicere -2 med 1-2x+\frac{1}{4}x^{2}.

$$y=6-\frac{9}{2}x+\frac{3}{2}x^{2}-\frac{1}{8}x^{3}-2+4x-\frac{1}{2}x^{2}$$

Subtraher 2 fra 6 for at få 4.

$$y=4-\frac{9}{2}x+\frac{3}{2}x^{2}-\frac{1}{8}x^{3}+4x-\frac{1}{2}x^{2}$$

Kombiner -\frac{9}{2}x og 4x for at få -\frac{1}{2}x.

$$y=4-\frac{1}{2}x+\frac{3}{2}x^{2}-\frac{1}{8}x^{3}-\frac{1}{2}x^{2}$$

Kombiner \frac{3}{2}x^{2} og -\frac{1}{2}x^{2} for at få x^{2}.

$$y=4-\frac{1}{2}x+x^{2}-\frac{1}{8}x^{3}$$