How To Simplify Fourth Roots: A Step-by-Step Guide

by Andrew McMorgan 51 views

Hey guys! Today, we're diving deep into the cool world of simplifying fourth roots, specifically tackling a beast like f7g9h144\sqrt[4]{f^7 g^9 h^{14}}. Don't let those exponents and the radical sign freak you out; we're going to break it down piece by piece. Simplifying radicals is all about finding perfect fourth powers inside the root and pulling them out. Think of it like this: if you have four of the same factor, you can take one out of the fourth root. We'll be using our exponent rules to make this whole process way easier. So, grab your calculators, maybe a snack, and let's get this math party started!

Understanding Fourth Roots and Exponents

Alright, let's get our heads around what a fourth root actually means before we jump into simplifying f7g9h144\sqrt[4]{f^7 g^9 h^{14}}. A fourth root is the inverse operation of raising a number to the power of four. So, if you have a number 'x' and you raise it to the fourth power (x⁴), its fourth root is 'x'. For example, the fourth root of 16 is 2 because 2⁴ = 16. When we see a radical symbol like …4\sqrt[4]{\dots}, it's asking us to find that number which, when multiplied by itself four times, gives us what's inside the radical. Now, let's talk exponents. Exponents tell us how many times to multiply a base number by itself. So, f7f^7 means fΓ—fΓ—fΓ—fΓ—fΓ—fΓ—ff \times f \times f \times f \times f \times f \times f.

Here's the crucial link between fourth roots and exponents that'll make simplifying f7g9h144\sqrt[4]{f^7 g^9 h^{14}} a breeze: a fourth root can be expressed as a fractional exponent. Specifically, x4\sqrt[4]{x} is the same as x1/4x^{1/4}. This means f7g9h144\sqrt[4]{f^7 g^9 h^{14}} is equivalent to (f7g9h14)1/4(f^7 g^9 h^{14})^{1/4}. When you have an exponent raised to another exponent, you multiply them. So, (xa)b=xaΓ—b(x^a)^b = x^{a \times b}. Applying this to our expression, we get f7Γ—(1/4)g9Γ—(1/4)h14Γ—(1/4)f^{7 \times (1/4)} g^{9 \times (1/4)} h^{14 \times (1/4)}, which simplifies to f7/4g9/4h14/4f^{7/4} g^{9/4} h^{14/4}.

This fractional exponent form is super handy because it directly relates to simplifying the radical. To simplify a fourth root, we look for exponents inside that are multiples of 4. For f7f^7, the largest multiple of 4 less than or equal to 7 is 4. So, we can rewrite f7f^7 as f4Γ—f3f^4 \times f^3. For g9g^9, the largest multiple of 4 less than or equal to 9 is 8, so g9=g8Γ—g1g^9 = g^8 \times g^1. And for h14h^{14}, the largest multiple of 4 less than or equal to 14 is 12, so h14=h12Γ—h2h^{14} = h^{12} \times h^2.

So, our original expression f7g9h144\sqrt[4]{f^7 g^9 h^{14}} can be rewritten as (f4Γ—f3)Γ—(g8Γ—g1)Γ—(h12Γ—h2)4\sqrt[4]{(f^4 \times f^3) \times (g^8 \times g^1) \times (h^{12} \times h^2)}. Using the property of radicals that aΓ—bn=anΓ—bn\sqrt[n]{a \times b} = \sqrt[n]{a} \times \sqrt[n]{b}, we can separate these terms: f44Γ—f34Γ—g84Γ—g14Γ—h124Γ—h24\sqrt[4]{f^4} \times \sqrt[4]{f^3} \times \sqrt[4]{g^8} \times \sqrt[4]{g^1} \times \sqrt[4]{h^{12}} \times \sqrt[4]{h^2}.

Now, the magic happens! Remember that xnn=x\sqrt[n]{x^n} = x? This means we can pull out the terms where the exponent inside matches the root index (which is 4 in this case). So, f44=f\sqrt[4]{f^4} = f, g84=g8/4=g2\sqrt[4]{g^8} = g^{8/4} = g^2, and h124=h12/4=h3\sqrt[4]{h^{12}} = h^{12/4} = h^3. The terms with exponents less than 4 (f3f^3, g1g^1, and h2h^2) stay inside the radical. Combining the terms we pulled out, we get fg2h3f g^2 h^3. The remaining terms inside the radical are f3g1h2f^3 g^1 h^2. Therefore, the simplified form of f7g9h144\sqrt[4]{f^7 g^9 h^{14}} is fg2h3f3gh24f g^2 h^3 \sqrt[4]{f^3 g h^2}. See? It's all about strategic rewriting and understanding those exponent rules!

Step-by-Step Simplification of f7g9h144\sqrt[4]{f^7 g^9 h^{14}}

Alright, gang, let's get down to business and simplify f7g9h144\sqrt[4]{f^7 g^9 h^{14}} step-by-step. We're aiming to pull out as much as possible from under that fourth root. Remember, for every group of four identical factors, we can take one out. This translates to exponents: for every exponent that's a multiple of 4, we can simplify it.

Step 1: Analyze the exponents inside the radical.

We have f7f^7, g9g^9, and h14h^{14}. We need to see how many groups of four we can make from each exponent.

  • For f7f^7: The largest multiple of 4 that is less than or equal to 7 is 4. So, we can write f7f^7 as f4Γ—f3f^4 \times f^3. The f4f^4 is a perfect fourth power, and the f3f^3 will remain inside.
  • For g9g^9: The largest multiple of 4 that is less than or equal to 9 is 8. So, we can write g9g^9 as g8Γ—g1g^8 \times g^1. The g8g^8 is a perfect fourth power (g8=(g2)4g^8 = (g^2)^4), and the g1g^1 (or just gg) will remain inside.
  • For h14h^{14}: The largest multiple of 4 that is less than or equal to 14 is 12. So, we can write h14h^{14} as h12Γ—h2h^{12} \times h^2. The h12h^{12} is a perfect fourth power (h12=(h3)4h^{12} = (h^3)^4), and the h2h^2 will remain inside.

Step 2: Rewrite the expression using these separations.

Now, substitute these back into our original expression: f7g9h144=(f4Γ—f3)Γ—(g8Γ—g1)Γ—(h12Γ—h2)4\sqrt[4]{f^7 g^9 h^{14}} = \sqrt[4]{(f^4 \times f^3) \times (g^8 \times g^1) \times (h^{12} \times h^2)}

Step 3: Separate the perfect fourth powers from the remainders.

Using the property abn=anΓ—bn\sqrt[n]{ab} = \sqrt[n]{a} \times \sqrt[n]{b}, we can split this into two parts: the part we can simplify and the part that stays inside.

Perfect fourth powers part: f4Γ—g8Γ—h124\sqrt[4]{f^4 \times g^8 \times h^{12}} Remainder part: f3Γ—g1Γ—h24\sqrt[4]{f^3 \times g^1 \times h^2}

So, our expression becomes: f4g8h124Γ—f3gh24\sqrt[4]{f^4 g^8 h^{12}} \times \sqrt[4]{f^3 g h^2}

Step 4: Simplify the perfect fourth powers part.

This is where we take factors out of the radical. Remember, xnn=x\sqrt[n]{x^n} = x, or more generally, xmn=xm/n\sqrt[n]{x^m} = x^{m/n}.

  • f44=f4/4=f1=f\sqrt[4]{f^4} = f^{4/4} = f^1 = f
  • g84=g8/4=g2\sqrt[4]{g^8} = g^{8/4} = g^2
  • h124=h12/4=h3\sqrt[4]{h^{12}} = h^{12/4} = h^3

So, the simplified outer part is fg2h3f g^2 h^3.

Step 5: Combine the simplified part with the remainder part.

Now, we put the terms we simplified outside the radical and the terms that remain inside back together.

The final simplified expression is: fg2h3f3gh24\mathbf{f g^2 h^3 \sqrt[4]{f^3 g h^2}}

See? We successfully simplified f7g9h144\sqrt[4]{f^7 g^9 h^{14}} by breaking down the exponents and pulling out all the perfect fourth powers. It’s all about breaking down the problem into smaller, manageable steps. Keep practicing, and you'll be a fourth-root-simplifying pro in no time!

Why Simplifying Radicals Matters

So, you might be wondering,