dumb question ( where did i go wrong? ) (1 Viewer)

[shuning]

suppose that

where Q(x) is a polynomial find the value of a

my working:
let x=0
LHS = a
RHS = 5

therefore a = 5.

but the answer is:
reminder theorem p(-2) = 5
-8 - 8 + a =5
a = 5+16
a = 21.

so yea.... WHERE THE FUCK DID I GO WRONG? i believe there are more than 1 solutions..... but its only a 2 mark Q... and the answer by my teacher only had 1 solution....

 

[annabackwards]

suppose that

where Q(x) is a polynomial find the value of a

my working:
let x=0
LHS = a
RHS = 5

therefore a = 5.

but the answer is:
reminder theorem p(-2) = 5
-8 - 8 + a =5
a = 5+16
a = 21.

so yea.... WHERE THE FUCK DID I GO WRONG? i believe there are more than 1 solutions..... but its only a 2 mark Q... and the answer by my teacher only had 1 solution....

The one in bold is the answer, as you do not know what the value of Qx(x) when x=0 is, so you have to eliminate it using the method in bold

 

[shuning]

回复: Re: dumb question ( where did i go wrong? )

The one in bold is the answer, as you do not know what the value of Q(x) when x=0 is, so you have to eliminate it using the method in bold

oh yea..... shit.... silly mistakes :burn:

 

[EvoRevolution]

u should let x = -2