Verify the Equality: 3^4 - (√25 - 2^2) - (2^3 - √4) Expression Analysis

Question

Indicate whether the equality is true or not.

34(2522)(234)=3425(2223)4 3^4-(\sqrt{25}-2^2)-(2^3-\sqrt{4})=3^4-\sqrt{25}-(2^2-2^3)-\sqrt{4}

Video Solution

Solution Steps

00:00 Is the equation correct?
00:02 Let's start solving the left side of the exercise
00:05 How do we open the parentheses of this expression?
00:09 The minus will multiply each term and reverse their signs
00:17 Let's apply it to our exercise
00:21 Square root of 25 and square of 2 reversed their signs
00:31 Let's continue simplifying the right side of the exercise
00:38 Let's apply the same method for opening parentheses
00:42 Let's compare all terms on both sides of the exercise
00:45 Let's reduce the equal terms
00:51 Let's solve 2 squared according to the laws of exponents
00:55 Let's substitute in our exercise
00:58 Let's solve 2 cubed according to the laws of exponents
01:02 Let's substitute in our exercise
01:06 Let's continue solving according to the correct order of operations
01:10 This is the final solution for the left side of the exercise
01:14 Now let's continue solving the right side of the exercise
01:17 Let's substitute the solution for 2 squared
01:20 Let's substitute the solution for 2 cubed
01:25 Let's continue solving according to the correct order of operations
01:28 This is the final solution for the right side of the exercise
01:31 According to our calculation, the equation is not correct
01:33 And this is the solution to the exercise

Step-by-Step Solution

To determine if the given equation is correct, we will simplify each expression in its sides separately,

This will be done while adhering to the order of operations which states that exponents come before multiplication and division, which come before addition and subtraction, and that parentheses come before all of these,

A. Let's start with the expression on the left side of the given equation:

34(2522)(234) 3^4-(\sqrt{25}-2^2)-(2^3-\sqrt{4}) We'll begin by simplifying the expressions inside the parentheses, this is done by calculating the numerical values of the terms with exponents (while remembering the definition of a root as an exponent stating that a root is actually an exponent), simultaneously we'll calculate the numerical value of the term with the exponent - the leftmost term:

34(2522)(234)=81(54)(82) 3^4-(\sqrt{25}-2^2)-(2^3-\sqrt{4}) =\\ 81-(5-4)-(8-2) We'll continue and finish simplifying the expressions inside the parentheses, meaning we'll perform the subtraction operations in them, then we'll perform the remaining subtraction operation:

81(54)(82)=8116=74 81-(5-4)-(8-2) =\\ 81-1-6=\\ 74 We have finished simplifying the expression on the left side of the given equation, let's summarize the simplification steps:

34(2522)(234)=8116=74 3^4-(\sqrt{25}-2^2)-(2^3-\sqrt{4}) =\\ 81-1-6=\\ 74 B. Let's continue with simplifying the expression on the right side of the given equation:

3425(2223)4 3^4-\sqrt{25}-(2^2-2^3)-\sqrt{4} We'll start by simplifying the expression inside the parentheses, this is done by calculating the numerical values of the terms with exponents (while remembering the definition of a root as an exponent stating that a root is actually an exponent), simultaneously we'll calculate the numerical values of the terms with exponents that are not in parentheses:

3425(2223)4=815(48)2 3^4-\sqrt{25}-(2^2-2^3)-\sqrt{4} =\\ 81-5-(4-8)-2 We'll continue and finish simplifying the expression inside the parentheses, meaning we'll perform the subtraction operation in it, then we'll perform the remaining subtraction operations:815(48)2=815(4)2=815+42=78 81-5-(4-8)-2 =\\ 81-5-(-4)-2 =\\ 81-5+4-2 =\\ 78 Note that the result of the subtraction operation in the parentheses yielded a negative result and therefore in the next step we kept this result in parentheses and then applied the multiplication law stating that multiplying a negative number by a negative number gives a positive result (so ultimately we get an addition operation), then, we performed the addition and subtraction operations in the resulting expression,

We have finished simplifying the expression on the right side of the given equation, let's summarize the simplification steps:

3425(2223)4=815(4)2=78 3^4-\sqrt{25}-(2^2-2^3)-\sqrt{4} =\\ 81-5-(-4)-2 =\\ 78

Let's now return to the given equation and substitute in its sides the results of simplifying the expressions detailed in A and B:

34(2522)(234)=3425(2223)474=78 3^4-(\sqrt{25}-2^2)-(2^3-\sqrt{4})=3^4-\sqrt{25}-(2^2-2^3)-\sqrt{4} \\ \downarrow\\ 74=78 Obviously this equation does not hold, meaning - we got a false statement,

Therefore the correct answer is answer B.

Answer

Not true