Question: Evaluate the expression for the given value of the variable. | − 4b − 8 | + ∣ − 1 − b² | + 2b³; b = − 2
Answer:
-11
Step-by-step explanation:
What we are required to do here is to find the value of the expression assuming that variable b = -2.
Bear in mind that, where you see the symbol "| ... |", enclosing a set of terms, the absolute value after performing whatever function with the enclosed terms is what is to be found. This means, after performing the operation, if you have a negative value, simply ignore the negative sign.
Now let's evaluate at b = -2
|- 4b - 8| + ∣-1 - b²| + 2b³ (given)
|- 4(-2) - 8| + ∣-1 - (-2)²| + 2(-2)³ (substitution)
|8 - 8| + ∣-1 - 4| + 2(-8)
|0| + ∣-5| - 16
0 + 5 - 16 (absolute value of -5 = 5)
= -11