Questions: Given R(x)=-x^3+2x^2-3x+4, evaluate R(-1)
Transcript text: 4. Given $R(x)=-x^{3}+2 x^{2}-3 x+4$, evaluate $R(-1)$
Solution
Solution Steps
To evaluate \( R(-1) \), substitute \(-1\) for \( x \) in the polynomial \( R(x) = -x^3 + 2x^2 - 3x + 4 \). Then, compute the result by performing the arithmetic operations.
Step 1: Substitute \( x = -1 \)
To evaluate \( R(-1) \), we substitute \(-1\) into the polynomial \( R(x) = -x^3 + 2x^2 - 3x + 4 \):
\[
R(-1) = -(-1)^3 + 2(-1)^2 - 3(-1) + 4
\]
Step 2: Calculate Each Term
Now, we calculate each term:
The first term: \(-(-1)^3 = -(-1) = 1\)
The second term: \(2(-1)^2 = 2(1) = 2\)
The third term: \(-3(-1) = 3\)
The fourth term: \(4\)
Step 3: Sum the Results
Now, we sum all the calculated terms:
\[
R(-1) = 1 + 2 + 3 + 4 = 10
\]