Which expression is a sum of cubes?
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Answer:
-27a³b⁶ + 8a⁹b¹²
Explanation:
Every term in the expression above every term is a perfect cube.
In the first term (-27a³b⁶), -27 is a perfect cube of -3 while the exponents of a and b are both divisible by three.
In the second term (8a⁹b¹²),8 is a perfect cube of 2 while the exponents of a and b are divisible by three.
If the index of a number is divisible by three to give a whole number, the result of finding the cube root is a whole number hence a perfect cube root.
Answer:
A) [tex]-27a^{3}b^{6} + 8a^{9}b^{12}[/tex]
Explanation:
-27 can be divided by -3 and the cube root of 8a^9 b^12 is 2a^3 b^4