Share

# Apply Division Algorithm to Find the Quotient Q(X) and Remainder R(X) on Dividing F(X) by G(X) in the Following (X) = 10x4 + 17x3 − 62x2 + 30x − 3, G(X) = 2x2 + 7x + 1 - Mathematics

Course

#### Question

Apply division algorithm to find the quotient q(x) and remainder r(x) on dividing f(x) by g(x) in the following f(x) = 10x4 + 17x3 − 62x2 + 30x − 3, g(x) = 2x2 + 7x + 1

#### Solution

We have

f(x) = 10x4 + 17x3 − 62x2 + 30x − 3

g(x) = 2x2 + 7x + 1

Therefore, quotient q(x) is of degree 4 - 2 = 2 and remainder r(x) is of degree less than 2

Let g(x) = ax2 + bx + c and

r(x) = px + q

Using division algorithm, we have

f(x) = g(x) x q(x) + r(x)

1Ox4+ 17x3 - 62x2 + 30x - 3 = (2x2 + 7x+ 1)(ax2 +bx+c)+ px+q

1Ox4+ 17x3 - 62x2 + 30x - 3 = 2ax4 + 7ax3 + ax2 + 2bx3 + 7bx2 + bx + 2cx2 + 7xc + c + px + q

1Ox4+ 17x3 - 62x2 + 30x - 3 = 2ax4 + 7ax3 + 2bx3 + ax2 + 7bx2 + 2cx2 + bx + 7xc +  px + c + q

a + 1Ox4+ 17x3 - 62x2 + 30x - 3 = 2ax4 + x3 (7a + 2b) + x2 (a + 7b + 2c) + x(b + 7c + p) + c + q

Equating the co-efficients of various powers x on both sides, we get

On equating the co-efficient of x

2a = 10

a=10/2

a = 5

On equating the co-efficient of x3

7a + 2b = 17

Substituting a = 5 we get

7 x 5 2b = 17

35 + 2b = 17

2b = 17 - 35

2b = -18

b=(-18)/2

b = -9

On equating the co-efficient of x2

a + 7b + 2c = -62

Substituting a = 5 and b = -9, we get

-9 + 7 x -2 + p = 30

-9 - 14 + p = 30

-23 + p = 30

p = 30 + 23

p = 53

On equating constant term, we get

c + q = -3

Substituting c = -2, we get

-2 + q = -3

q = -3 + 2

q = -1

Therefore, quotient q(x) = ax2 + bx + c

= 5x2 - 9x - 2

Remainder r(x) = px + q

= 53x - 1

Hence, the quotient and remainder are q(x) = 5x2 - 9x - 2 and r(x) = 53x - 1

Is there an error in this question or solution?