Problem

Solve for x (5x-4)^(2/3)=x^(1/3)

The problem provided is a mathematical equation where you have a variable x involved in both sides of the equation. Your task is to find the value(s) of x that satisfy the equation. The equation involves fractional exponents, which means you'll likely need to manipulate the equation and possibly use techniques that deal with exponents and roots in order to isolate the variable and solve for x.

$\left(\left(\right. 5 x - 4 \left.\right)\right)^{\frac{2}{3}} = x^{\frac{1}{3}}$

Answer

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Solution:

Step:1

Raise both sides of the equation to the power of 3 to clear the fractional exponents.

$((5x-4)^{\frac{2}{3}})^{3} = (x^{\frac{1}{3}})^{3}$

Step:2

Apply the power of a power rule to the left side of the equation.

Step:2.1

Utilize the rule $(a^{m})^{n} = a^{mn}$.

$((5x-4)^{\frac{2}{3} \cdot 3}) = (x^{\frac{1}{3}})^{3}$

Step:2.2

Simplify by canceling out the 3s.

Step:2.2.1

Perform the cancellation.

$((5x-4)^{\frac{2}{\cancel{3}} \cdot \cancel{3}}) = (x^{\frac{1}{3}})^{3}$

Step:2.2.2

Rewrite the simplified expression.

$(5x-4)^{2} = (x^{\frac{1}{3}})^{3}$

Step:3

Simplify the right side of the equation.

Step:3.1

Apply the power of a power rule to the right side.

Step:3.1.1

Use the rule $(a^{m})^{n} = a^{mn}$.

$(5x-4)^{2} = x^{\frac{1}{3} \cdot 3}$

Step:3.1.2

Simplify by canceling out the 3s.

Step:3.1.2.1

Perform the cancellation.

$(5x-4)^{2} = x^{\frac{1}{\cancel{3}} \cdot \cancel{3}}$

Step:3.1.2.2

Rewrite the simplified expression.

$(5x-4)^{2} = x^{1}$

Step:3.2

Simplify further.

$(5x-4)^{2} = x$

Step:4

Isolate the terms with x on one side.

Step:4.1

Subtract x from both sides.

$(5x-4)^{2} - x = 0$

Step:4.2

Expand and simplify.

Step:4.2.1

Express $(5x-4)^{2}$ as $(5x-4)(5x-4)$.

$(5x-4)(5x-4) - x = 0$

Step:4.2.2

Use the FOIL method to expand.

Step:4.2.2.1

Distribute each term.

$5x(5x-4) - 4(5x-4) - x = 0$

Step:4.2.2.2

Continue distributing.

$5x(5x) + 5x(-4) - 4(5x) - 4(-4) - x = 0$

Step:4.2.2.3

Complete the distribution.

$5x(5x) + 5x(-4) - 4(5x) - 4(-4) - x = 0$

Step:4.2.3

Combine like terms.

Step:4.2.3.1

Simplify each term.

Step:4.2.3.1.1

Multiply using the commutative property.

$5 \cdot 5x \cdot x + 5x(-4) - 4(5x) - 4(-4) - x = 0$

Step:4.2.3.1.2

Add the exponents when multiplying x by x.

Step:4.2.3.1.2.1

Combine x terms.

$5 \cdot 5(x \cdot x) + 5x(-4) - 4(5x) - 4(-4) - x = 0$

Step:4.2.3.1.2.2

Multiply x by x.

$5 \cdot 5x^{2} + 5x(-4) - 4(5x) - 4(-4) - x = 0$

Step:4.2.3.1.3

Multiply 5 by 5.

$25x^{2} + 5x(-4) - 4(5x) - 4(-4) - x = 0$

Step:4.2.3.1.4

Multiply -4 by 5.

$25x^{2} - 20x - 4(5x) - 4(-4) - x = 0$

Step:4.2.3.1.5

Multiply 5 by -4.

$25x^{2} - 20x - 20x - 4(-4) - x = 0$

Step:4.2.3.1.6

Multiply -4 by -4.

$25x^{2} - 20x - 20x + 16 - x = 0$

Step:4.2.3.2

Combine the x terms.

$25x^{2} - 40x + 16 - x = 0$

Step:4.3

Combine the remaining x terms.

$25x^{2} - 41x + 16 = 0$

Step:5

Factor the quadratic equation.

Step:5.1

Look for two numbers that multiply to $25 \cdot 16 = 400$ and add up to -41.

Step:5.1.1

Factor -41 out of -41x.

$25x^{2} - 41x + 16 = 0$

Step:5.1.2

Split -41 into -16 and -25.

$25x^{2} + (-16 - 25)x + 16 = 0$

Step:5.1.3

Distribute the x term.

$25x^{2} - 16x - 25x + 16 = 0$

Step:5.2

Factor by grouping.

Step:5.2.1

Group the first two and the last two terms.

$(25x^{2} - 16x) - (25x - 16) = 0$

Step:5.2.2

Factor out the GCF from each group.

$x(25x - 16) - 1(25x - 16) = 0$

Step:5.3

Factor out the common binomial factor.

$(25x - 16)(x - 1) = 0$

Step:6

Apply the zero-product property.

$25x - 16 = 0$ or $x - 1 = 0$

Step:7

Solve for x when $25x - 16 = 0$.

Step:7.1

Set the expression equal to zero.

$25x - 16 = 0$

Step:7.2

Isolate x.

Step:7.2.1

Add 16 to both sides.

$25x = 16$

Step:7.2.2

Divide by 25.

Step:7.2.2.1

Divide both sides by 25.

$\frac{25x}{25} = \frac{16}{25}$

Step:7.2.2.2

Simplify the equation.

$x = \frac{16}{25}$

Step:8

Solve for x when $x - 1 = 0$.

Step:8.1

Set the expression equal to zero.

$x - 1 = 0$

Step:8.2

Add 1 to both sides.

$x = 1$

Step:9

Combine the solutions.

$x = \frac{16}{25}$ or $x = 1$

Step:10

Present the solution in various forms.

Exact Form: $x = \frac{16}{25}$ or $x = 1$ Decimal Form: $x = 0.64$ or $x = 1$

Knowledge Notes:

  1. Fractional Exponents: The expression $a^{\frac{m}{n}}$ is equivalent to the nth root of $a$ raised to the power m, i.e., $\sqrt[n]{a^m}$.

  2. Power of a Power Rule: When raising a power to another power, multiply the exponents, $(a^m)^n = a^{mn}$.

  3. Zero-Product Property: If the product of two factors is zero, then at least one of the factors must be zero, i.e., if $ab = 0$, then $a = 0$ or $b = 0$.

  4. FOIL Method: A technique for multiplying two binomials, which stands for First, Outer, Inner, Last, representing the terms that are multiplied together.

  5. Factoring by Grouping: A method used to factor polynomials with four terms by grouping pairs of terms that have a common factor.

  6. Solving Quadratic Equations: Quadratic equations can often be solved by factoring, completing the square, or using the quadratic formula. In this case, factoring was used.

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