Question

sy

想請問為什麼能改寫成黃色部份？以及降階是如何操作的 ［學測數學複習：多項式］

[EX] f(x) P & "x q ( x + 9) | P₁ (x) = x + 2 113 14 1; b 3 10 * 4
[ x ] f (x 17 x
| (x² - 9 ) 2 P~ ( x ) = X - 2 11½ 14 33 63 17
Fu f(x)i & ux (x²+4) (x² - 4) 2 K3 (X) = ?
f=Qx9+R
f(x) = (x²+ 4) Q₁ + (x+2) b
= (4-4) Q~+ (X-2)
= (x² + 4 ) ( x² - 4) Q 3 + ax² + by ² + u x + d
= (x² + 4) (x² - 4) Q3 + (x² + 4) (qx+m)+(X+²)
f(2)=0=8 (29+m) +9 ? 49+2m=1&m=-4,
f(~~) = -4 -8 (-29 +m)
49-2m=1
i i R 3 (X) = (x² + ~ ) ( 0 X - 1/2) + (x + 2) #1
M=
2,9=
0