Question

If the operation 'o' is defined as \( (a \, o \, b) = a^3 + b^3 \), then what is \( 4 \, o \, (1 \, o \, 2) \)?

• A. 729
• B. 793
• C. 783
• D. 792

Hint:

When an operation is defined as \( (a \, o \, b) = a^3 + b^3 \), always compute the cubes and then add them.

Answer 1

The Correct Option is B

We are given that \( (a \, o \, b) = a^3 + b^3 \), so we first need to find \( 1 \, o \, 2 \). Using the given operation: \[ 1 \, o \, 2 = 1^3 + 2^3 = 1 + 8 = 9 \] Now, we need to find \( 4 \, o \, 9 \): \[ 4 \, o \, 9 = 4^3 + 9^3 = 64 + 729 = 793 \] Thus, the correct answer is \( 793 \).