Solve (4·7)^9 + 2^7/2^4 + (8^2)^5: Complex Exponent Calculation

Question

(47)9+2724+(82)5= (4\cdot7)^9+\frac{2^7}{2^4}+(8^2)^5=

Video Solution

Solution Steps

00:00 Solve
00:03 When there's a power over a product of numbers, all terms are raised to that power
00:08 When dividing powers with equal bases
00:13 The power of the result equals the difference of the powers
00:19 Let's use this formula in our exercise
00:23 When there's a power of a power, the resulting power is the product of the powers
00:29 Let's use this formula in our exercise
00:33 Let's calculate all the powers
00:43 And this is the solution to the question

Step-by-Step Solution

In order to solve the problem we must use two power laws, as shown below:

A. Power property for terms with identical bases:

aman=amn \frac{a^m}{a^n}=a^{m-n} B. Power property for an exponent raised to another exponent:

(am)n=amn (a^m)^n=a^{m\cdot n}

We will apply these two power laws to the problem in two steps:

Let's start by applying the power law specified in A to the second term from the left in the given problem:

2724=274=23 \frac{2^7}{2^4}=2^{7-4}=2^3 In the first step we apply the power law specified in A and then proceed to simplify the resulting expression,

We then advance to the next step and apply the power law specified in B to the third term from the left in the given problem :

(82)5=825=810 (8^2)^5=8^{2\cdot5}=8^{10} In the first stage we apply the power law specified in B and then proceed to simplify the resulting expression,

Let's summarize the two steps listed above to solve the general problem:

(47)9+2724+(82)5=(47)9+23+810 (4\cdot7)^9+\frac{2^7}{2^4}+(8^2)^5= (4\cdot7)^9+2^3+8^{10} In the final step, we calculate the result of multiplying the terms within the parentheses in the first term from the left:

(47)9+23+810=289+23+810 (4\cdot7)^9+2^3+8^{10}=28^9+2^3+8^{10} Therefore, the correct answer is option c.

Answer

289+23+810 28^9+2^3+8^{10}