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Consider this expression:
[tex]\[ \sqrt{a^3-7}+|b| \][/tex]

When [tex]\( a=2 \)[/tex] and [tex]\( b=-4 \)[/tex], the value of the expression is [tex]\(\square\)[/tex]



Answer :

Sure, let's solve the given expression step by step:

Given the expression:
[tex]\[ \sqrt{a^3 - 7} + |b| \][/tex]

where [tex]\( a = 2 \)[/tex] and [tex]\( b = -4 \)[/tex].

1. Calculate [tex]\( a^3 \)[/tex]:

[tex]\[ a^3 = 2^3 = 8 \][/tex]

2. Substitute [tex]\( a^3 \)[/tex] into the expression:

[tex]\[ a^3 - 7 = 8 - 7 = 1 \][/tex]

3. Calculate the square root:

[tex]\[ \sqrt{1} = 1.0 \][/tex]

4. Calculate the absolute value of [tex]\( b \)[/tex]:

[tex]\[ |b| = |-4| = 4 \][/tex]

5. Add the results together:

[tex]\[ \sqrt{1} + |b| = 1.0 + 4 = 5.0 \][/tex]

Therefore, when [tex]\( a = 2 \)[/tex] and [tex]\( b = -4 \)[/tex], the value of the expression is [tex]\( \boxed{5.0} \)[/tex].