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]\(\boxed{\ }\)[/tex]



Answer :

Let's evaluate the given expression step by step with the values [tex]\( a = 2 \)[/tex] and [tex]\( b = -4 \)[/tex].

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

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

Given [tex]\( a = 2 \)[/tex]:
[tex]\[ a^3 = 2^3 = 8 \][/tex]

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

[tex]\[ \sqrt{8 - 7} + |b| \][/tex]

Step 3: Simplify [tex]\( 8 - 7 \)[/tex].

[tex]\[ 8 - 7 = 1 \][/tex]

So the expression now becomes:
[tex]\[ \sqrt{1} + |b| \][/tex]

Step 4: Compute the square root of 1.

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

Step 5: Calculate the absolute value of [tex]\( b \)[/tex].

Given [tex]\( b = -4 \)[/tex]:
[tex]\[ |b| = |-4| = 4 \][/tex]

Step 6: Substitute the calculated values into the expression.

[tex]\[ 1 + 4 \][/tex]

Step 7: Add the values together.

[tex]\[ 1 + 4 = 5 \][/tex]

Therefore, the value of the expression is:
[tex]\[ \boxed{5} \][/tex]