Math worksheet for rationalizing denominators with various fractions involving square roots.
Worksheet titled "Rationalizing Denominators" with math problems to rationalize fractions and simplify when possible.
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Show Answer Key & Explanations
Step-by-step solution for: Rationalize Denominator Worksheets (printable, online, answers ...
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Show Answer Key & Explanations
Step-by-step solution for: Rationalize Denominator Worksheets (printable, online, answers ...
You're asked to rationalize the denominator of each fraction — that means eliminate any square roots from the denominator by multiplying numerator and denominator by a suitable form of 1 (usually the radical itself or its conjugate). Then simplify if possible.
Let’s go through each one step by step.
---
Multiply numerator and denominator by $\sqrt{2}$:
$$
\frac{1}{\sqrt{2}} \cdot \frac{\sqrt{2}}{\sqrt{2}} = \frac{\sqrt{2}}{2}
$$
✔ Answer: $\boxed{\dfrac{\sqrt{2}}{2}}$
---
Multiply numerator and denominator by $\sqrt{2}$:
$$
\frac{6}{\sqrt{2}} \cdot \frac{\sqrt{2}}{\sqrt{2}} = \frac{6\sqrt{2}}{2} = 3\sqrt{2}
$$
✔ Answer: $\boxed{3\sqrt{2}}$
---
Multiply numerator and denominator by $\sqrt{3}$:
$$
\frac{2}{\sqrt{3}} \cdot \frac{\sqrt{3}}{\sqrt{3}} = \frac{2\sqrt{3}}{3}
$$
✔ Answer: $\boxed{\dfrac{2\sqrt{3}}{3}}$
---
First, simplify $\sqrt{12} = \sqrt{4 \cdot 3} = 2\sqrt{3}$, so:
$$
\frac{1}{3 \cdot 2\sqrt{3}} = \frac{1}{6\sqrt{3}}
$$
Now rationalize:
$$
\frac{1}{6\sqrt{3}} \cdot \frac{\sqrt{3}}{\sqrt{3}} = \frac{\sqrt{3}}{6 \cdot 3} = \frac{\sqrt{3}}{18}
$$
✔ Answer: $\boxed{\dfrac{\sqrt{3}}{18}}$
---
Multiply numerator and denominator by $\sqrt{5}$:
$$
\frac{15}{\sqrt{5}} \cdot \frac{\sqrt{5}}{\sqrt{5}} = \frac{15\sqrt{5}}{5} = 3\sqrt{5}
$$
✔ Answer: $\boxed{3\sqrt{5}}$
---
Multiply numerator and denominator by $\sqrt{6}$:
$$
\frac{12}{\sqrt{6}} \cdot \frac{\sqrt{6}}{\sqrt{6}} = \frac{12\sqrt{6}}{6} = 2\sqrt{6}
$$
✔ Answer: $\boxed{2\sqrt{6}}$
---
Multiply numerator and denominator by $\sqrt{7}$:
$$
\frac{42}{\sqrt{7}} \cdot \frac{\sqrt{7}}{\sqrt{7}} = \frac{42\sqrt{7}}{7} = 6\sqrt{7}
$$
✔ Answer: $\boxed{6\sqrt{7}}$
---
Multiply numerator and denominator by $\sqrt{2}$:
$$
\frac{8}{3\sqrt{2}} \cdot \frac{\sqrt{2}}{\sqrt{2}} = \frac{8\sqrt{2}}{3 \cdot 2} = \frac{8\sqrt{2}}{6} = \frac{4\sqrt{2}}{3}
$$
✔ Answer: $\boxed{\dfrac{4\sqrt{2}}{3}}$
---
Multiply numerator and denominator by $\sqrt{11}$:
$$
\frac{2}{\sqrt{11}} \cdot \frac{\sqrt{11}}{\sqrt{11}} = \frac{2\sqrt{11}}{11}
$$
✔ Answer: $\boxed{\dfrac{2\sqrt{11}}{11}}$
---
Multiply numerator and denominator by $\sqrt{7}$:
$$
\frac{3}{2\sqrt{7}} \cdot \frac{\sqrt{7}}{\sqrt{7}} = \frac{3\sqrt{7}}{2 \cdot 7} = \frac{3\sqrt{7}}{14}
$$
✔ Answer: $\boxed{\dfrac{3\sqrt{7}}{14}}$
---
## ✔ Final Answers:
1. $\boxed{\dfrac{\sqrt{2}}{2}}$
2. $\boxed{3\sqrt{2}}$
3. $\boxed{\dfrac{2\sqrt{3}}{3}}$
4. $\boxed{\dfrac{\sqrt{3}}{18}}$
5. $\boxed{3\sqrt{5}}$
6. $\boxed{2\sqrt{6}}$
7. $\boxed{6\sqrt{7}}$
8. $\boxed{\dfrac{4\sqrt{2}}{3}}$
9. $\boxed{\dfrac{2\sqrt{11}}{11}}$
10. $\boxed{\dfrac{3\sqrt{7}}{14}}$
---
## 💡 Key Concept:
To rationalize a denominator with a single square root, multiply numerator and denominator by that same square root. This turns the denominator into a rational number (since $\sqrt{a} \cdot \sqrt{a} = a$).
If there’s a coefficient (like $3\sqrt{2}$), treat it as part of the denominator — still multiply by the radical only (not the coefficient) to eliminate the root.
Always simplify the resulting fraction if possible!
Let’s go through each one step by step.
---
1. $\frac{1}{\sqrt{2}}$
Multiply numerator and denominator by $\sqrt{2}$:
$$
\frac{1}{\sqrt{2}} \cdot \frac{\sqrt{2}}{\sqrt{2}} = \frac{\sqrt{2}}{2}
$$
✔ Answer: $\boxed{\dfrac{\sqrt{2}}{2}}$
---
2. $\frac{6}{\sqrt{2}}$
Multiply numerator and denominator by $\sqrt{2}$:
$$
\frac{6}{\sqrt{2}} \cdot \frac{\sqrt{2}}{\sqrt{2}} = \frac{6\sqrt{2}}{2} = 3\sqrt{2}
$$
✔ Answer: $\boxed{3\sqrt{2}}$
---
3. $\frac{2}{\sqrt{3}}$
Multiply numerator and denominator by $\sqrt{3}$:
$$
\frac{2}{\sqrt{3}} \cdot \frac{\sqrt{3}}{\sqrt{3}} = \frac{2\sqrt{3}}{3}
$$
✔ Answer: $\boxed{\dfrac{2\sqrt{3}}{3}}$
---
4. $\frac{1}{3\sqrt{12}}$
First, simplify $\sqrt{12} = \sqrt{4 \cdot 3} = 2\sqrt{3}$, so:
$$
\frac{1}{3 \cdot 2\sqrt{3}} = \frac{1}{6\sqrt{3}}
$$
Now rationalize:
$$
\frac{1}{6\sqrt{3}} \cdot \frac{\sqrt{3}}{\sqrt{3}} = \frac{\sqrt{3}}{6 \cdot 3} = \frac{\sqrt{3}}{18}
$$
✔ Answer: $\boxed{\dfrac{\sqrt{3}}{18}}$
---
5. $\frac{15}{\sqrt{5}}$
Multiply numerator and denominator by $\sqrt{5}$:
$$
\frac{15}{\sqrt{5}} \cdot \frac{\sqrt{5}}{\sqrt{5}} = \frac{15\sqrt{5}}{5} = 3\sqrt{5}
$$
✔ Answer: $\boxed{3\sqrt{5}}$
---
6. $\frac{12}{\sqrt{6}}$
Multiply numerator and denominator by $\sqrt{6}$:
$$
\frac{12}{\sqrt{6}} \cdot \frac{\sqrt{6}}{\sqrt{6}} = \frac{12\sqrt{6}}{6} = 2\sqrt{6}
$$
✔ Answer: $\boxed{2\sqrt{6}}$
---
7. $\frac{42}{\sqrt{7}}$
Multiply numerator and denominator by $\sqrt{7}$:
$$
\frac{42}{\sqrt{7}} \cdot \frac{\sqrt{7}}{\sqrt{7}} = \frac{42\sqrt{7}}{7} = 6\sqrt{7}
$$
✔ Answer: $\boxed{6\sqrt{7}}$
---
8. $\frac{8}{3\sqrt{2}}$
Multiply numerator and denominator by $\sqrt{2}$:
$$
\frac{8}{3\sqrt{2}} \cdot \frac{\sqrt{2}}{\sqrt{2}} = \frac{8\sqrt{2}}{3 \cdot 2} = \frac{8\sqrt{2}}{6} = \frac{4\sqrt{2}}{3}
$$
✔ Answer: $\boxed{\dfrac{4\sqrt{2}}{3}}$
---
9. $\frac{2}{\sqrt{11}}$
Multiply numerator and denominator by $\sqrt{11}$:
$$
\frac{2}{\sqrt{11}} \cdot \frac{\sqrt{11}}{\sqrt{11}} = \frac{2\sqrt{11}}{11}
$$
✔ Answer: $\boxed{\dfrac{2\sqrt{11}}{11}}$
---
10. $\frac{3}{2\sqrt{7}}$
Multiply numerator and denominator by $\sqrt{7}$:
$$
\frac{3}{2\sqrt{7}} \cdot \frac{\sqrt{7}}{\sqrt{7}} = \frac{3\sqrt{7}}{2 \cdot 7} = \frac{3\sqrt{7}}{14}
$$
✔ Answer: $\boxed{\dfrac{3\sqrt{7}}{14}}$
---
## ✔ Final Answers:
1. $\boxed{\dfrac{\sqrt{2}}{2}}$
2. $\boxed{3\sqrt{2}}$
3. $\boxed{\dfrac{2\sqrt{3}}{3}}$
4. $\boxed{\dfrac{\sqrt{3}}{18}}$
5. $\boxed{3\sqrt{5}}$
6. $\boxed{2\sqrt{6}}$
7. $\boxed{6\sqrt{7}}$
8. $\boxed{\dfrac{4\sqrt{2}}{3}}$
9. $\boxed{\dfrac{2\sqrt{11}}{11}}$
10. $\boxed{\dfrac{3\sqrt{7}}{14}}$
---
## 💡 Key Concept:
To rationalize a denominator with a single square root, multiply numerator and denominator by that same square root. This turns the denominator into a rational number (since $\sqrt{a} \cdot \sqrt{a} = a$).
If there’s a coefficient (like $3\sqrt{2}$), treat it as part of the denominator — still multiply by the radical only (not the coefficient) to eliminate the root.
Always simplify the resulting fraction if possible!
Parent Tip: Review the logic above to help your child master the concept of rationalize denominator worksheet.