on dividing x3-3x2+x+2 by a polynomial g(x) the quotient and remainder were x-3 and 4 respectively find g of x
Answers
Answer:
g(x)=x
2
−x+1
Step-by-step explanation:
Dividend =p(x)=x
3
−3x
2
+x+2
Quotient =q(x)=x−2
Remainder =r(x)=2x+4
By division algorithm, p(x)=q(x)g(x)+r(x)
⇒g(x)=
q(x)
p(x)−r(x)
⇒g(x)=
x−2
x
3
−3x
2
+x+2+2x−4
⇒g(x)=
x−2
x
3
−3x
2
+3x−2
So, g(x)=x
2
−x+1
Given:
Dividend = x³ - 3x² + x + 2
Quotient = x - 3
Reamainder = 4
To find:
Divisor g(x)
Solution:
Dividend = Divisor × Quotient + Remainder
x³ - 3x² + x + 2 = g(x) × (x - 3) + 4
x³ - 3x² + x - 2 = g(x) × (x - 3)
g(x) = (x³ - 3x² + x - 2) / (x - 3)
x - 3) x³ - 3x² + x - 2 ( x² + 1
x³ - 3x² ↓ ↓
(-) (+)
0 0 x - 2
x - 3
(-) (+)
1
There is some error in the given data because we are getting remainder = 1.
The given data must be
Dividend = x³ - 3x² + x + 2
Quotient = x - 3
Reamainder = 5
Dividend = Divisor × Quotient + Remainder
x³ - 3x² + x + 2 = g(x) × (x - 3) + 5
x³ - 3x² + x - 3 = g(x) × (x - 3)
g(x) = (x³ - 3x² + x - 3) / (x - 3)
x - 3) x³ - 3x² + x - 3 ( x² + 1
x³ - 3x² ↓ ↓
(-) (+)
0 0 x - 3
x - 3
(-) (+)
0
So, g(x) = x² + 1