Simplify (x²×y³×z⁴)²: Advanced Exponent Expression

Question

(x2×y3×z4)2= ? (x^2\times y^3\times z^4)^2=\text{ ?}

Video Solution

Solution Steps

00:00 Solve the following problem
00:02 When there is a power over a power, the combined power is the product of the powers
00:05 When there is a power over a product of multiple terms, all terms are raised to that power

Step-by-Step Solution

Let's solve this in two stages. In the first stage, we'll use the rule for power of a product in parentheses:

(ab)n=anbn (a\cdot b)^n=a^n\cdot b^n

This rule states that, when raising a product in parentheses to a power, the power applies to each factor of the product when opening the parentheses.

Let's apply this rule to our problem:

(x2y3z4)2=(x2)2(y3)2(z4)2 (x^2\cdot y^3\cdot z^4)^2=(x^2)^2\cdot(y^3)^2\cdot(z^4)^2

In our case, when expanding the parentheses, we apply the power to each factor of the product separately. However, since each of the factors are raised to a power, we do this carefully and use parentheses.

Next, we'll use the power rule for a power of a power:

(bm)n=bmn (b^m)^n=b^{m\cdot n}

Let's apply this law to the expression we have:

(x2)2(y3)2(z4)2=x22y32z42=x4y6z8 (x^2)^2\cdot(y^3)^2\cdot(z^4)^2=x^{2\cdot2}\cdot y^{3\cdot2}\cdot z^{4\cdot2}=x^4\cdot y^6\cdot z^8

In the second stage we perform the multiplication operation in the power exponents of the factors we obtained.

Therefore, the correct answer is answer D.

Note:

From the above formulation of the power law for parentheses, it might seem that it only refers to two factors in a product within parentheses, but in fact it is valid for a power of a product of multiple factors in parentheses, as demonstrated in this problem.

It would be a good exercise to prove that if the above law is valid for a power of a product of two factors in parentheses (as it is formulated above), then it is also valid for a power of a product of multiple factors in parentheses (for example - three factors, etc.).

Answer

x4y6z8 x^4y^6z^8