Evaluate the expression:

[tex]\[ a y^2 - y^3 \][/tex]

for [tex]\( a = 8.8 \)[/tex] and [tex]\( y = -1.2 \)[/tex].



Answer :

Certainly! Let's solve the expression [tex]\( a y^2 - y^3 \)[/tex] step-by-step for [tex]\( a = 8.8 \)[/tex] and [tex]\( y = -1.2 \)[/tex].

1. Substitute the given values into the expression:
[tex]\[ 8.8 \cdot (-1.2)^2 - (-1.2)^3 \][/tex]

2. Calculate [tex]\( (-1.2)^2 \)[/tex]:
[tex]\[ (-1.2)^2 = 1.44 \][/tex]

3. Multiply [tex]\( 8.8 \)[/tex] by [tex]\( 1.44 \)[/tex]:
[tex]\[ 8.8 \cdot 1.44 = 12.672 \][/tex]
This is the value of the term [tex]\( a y^2 \)[/tex].

4. Calculate [tex]\( (-1.2)^3 \)[/tex]:
[tex]\[ (-1.2)^3 = -1.728 \][/tex]
Note that the actual cubic value is very close to [tex]\(-1.728\)[/tex], but we need to maintain accuracy with significant digits.

5. Form the expression with the two calculated terms:
[tex]\[ 12.672 - (-1.728) \][/tex]

6. Subtract the cubic term (keep in mind subtracting a negative value means adding its positive counterpart):
[tex]\[ 12.672 + 1.728 = 14.4 \][/tex]

Therefore, the answer is [tex]\( 14.4 \)[/tex].

So, to summarize:

- The term [tex]\( a y^2 \)[/tex] evaluates to [tex]\( 12.672 \)[/tex].
- The term [tex]\( y^3 \)[/tex] evaluates to [tex]\( -1.728 \)[/tex].
- Subtracting [tex]\( y^3 \)[/tex] from [tex]\( a y^2 \)[/tex], we get the final result of [tex]\( 14.4 \)[/tex].