What is the remainder when $P(x)=-x^3-2x^2-3x+8$ is divided by $x+2$? - HSC - SSCE Mathematics Extension 1 - Question 3 - 2021 - Paper 1
Question 3
What is the remainder when $P(x)=-x^3-2x^2-3x+8$ is divided by $x+2$?
Worked Solution & Example Answer:What is the remainder when $P(x)=-x^3-2x^2-3x+8$ is divided by $x+2$? - HSC - SSCE Mathematics Extension 1 - Question 3 - 2021 - Paper 1
Step 1
Find the value of $x$
96%
114 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
To find the remainder when P(x) is divided by x+2, we apply the Remainder Theorem, which states that the remainder of the division of a polynomial P(x) by x−c is P(c). Here, we substitute x=−2.
Step 2
Evaluate $P(-2)$
99%
104 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
Now, substituting −2 into P(x):
P(−2)=−(−2)3−2(−2)2−3(−2)+8
Calculating this, we have:
−(−2)3=−(−8)=8
−2(−2)2=−2(4)=−8
−3(−2)=6
So,
P(−2)=8−8+6+8=14
Step 3
State the remainder
96%
101 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
Thus, the remainder when dividing P(x) by x+2 is 14.