Question

If p(x)=8x3-2x2-x-4 then find p(1),p(-2),p(1/2),p(-1)

Answer 1

Answer:

Step-by-step explanation:

p(1) = 8 - 2 - 1 - 4 = 1

p(- 1) = - 8 - 2 + 1 - 4 = - 13

p(- 2) = - 64 - 8 + 2 - 4 = - 74

p(1 / 2) = 1 - 1 / 2 - 1 / 2 - 4 = - 4.

Answer 2

Answer:

Given:

• p(x)=8x3-2x2-x-4

To find :

• different values for 'x' p(1),p(-2),p(1/2),p(-1)

Solving Question:

 We are given the polynomial and we are asked to find the values of the polynomial at different values for 'x'.

   It could be solved by substituting the values in place of 'x'

Solution:

p(x)=8x3-2x2-x-4

first, p(1)

⇒ 8(1)³ -2(1)²-1-4

or, 8 -2 -1 -4

or, 8-7

or, 1

p(x)=8x3-2x2-x-4

Second, p(-2)

⇒ 8(-2)³ -2(-2)² -(-2) -4

or, 8*(-8) -2(4) +2 -4

or, -64 -8 +2-4

or, -74

p(x)=8x3-2x2-x-4

Third, p(1/2)

⇒ 8(1/2)³ -2(1/2)² -1/2 -4

or, 8(1/8) -2(1/4) -1/2 -4

or,1 -1/2 - 1/2 -4

or, ( 2 -1 -1 -8)/2 [ L.C.M =2]

or, -8/2

or, -4

p(x)=8x3-2x2-x-4

Fourth, p(-1)

⇒ 8(-1)³ -2(-1)² -(-1) -4

or, -8 -2 +1 -4

or, 13