Operations with Radicals
An architect in Querétaro designs a triangular skylight and finds that its height is $\sqrt{18}+\sqrt{6}$ meters. How does she calculate the exact area without approximating with a calculator? For that you need to operate with radicals: add them, multiply them, and remove them from denominators. By the end of this page you will answer that question.
Like radicals: adding and subtracting
Simplify the following mathematical expression by extracting factors from the radicals and grouping like terms: $5\sqrt{12} - \sqrt{27} + 2\sqrt{75}$
Simplify the following mathematical expression by extracting factors from the radicals and grouping like terms:
$5\sqrt{12} - \sqrt{27} + 2\sqrt{75}$
Extract all possible factors from the following radicals and simplify the resulting expression to obtain a single term: $3\sqrt{80} - 2\sqrt{45} + \sqrt{20}$
Extract all possible factors from the following radicals and simplify the resulting expression to obtain a single term:
$3\sqrt{80} - 2\sqrt{45} + \sqrt{20}$
Extracting and introducing factors
Extract all possible factors from the following radicals to obtain the simplest expression: a) $\sqrt{72x^4y^3}$ b) $\sqrt[3]{128a^5}$
Extract all possible factors from the following radicals to obtain the simplest expression:
- a) $\sqrt{72x^4y^3}$
- b) $\sqrt[3]{128a^5}$
Insert the factors inside the radical in the following expressions: a) $3 \sqrt{5x}$ b) $2a^2 \sqrt[3]{3a}$
Insert the factors inside the radical in the following expressions:
- a) $3 \sqrt{5x}$
- b) $2a^2 \sqrt[3]{3a}$
Find the height ($h$) of a triangular solar panel if we know that its area is $\sqrt{24}$ square meters and its base measures $\sqrt{2}$ meters. Remember that the area…
Find the height ($h$) of a triangular solar panel if we know that its area is $\sqrt{24}$ square meters and its base measures $\sqrt{2}$ meters. Remember that the area of a triangle is calculated as $A = \frac{\text{base} \times \text{altura}}{2}$. Express the result simplifying the radicals.
Multiplying and dividing radicals
Perform the following operations with radicals of the same index and express the result in the simplest possible form: a) $\sqrt[4]{2} \times \sqrt[4]{8}$ b)…
Perform the following operations with radicals of the same index and express the result in the simplest possible form:
- a) $\sqrt[4]{2} \times \sqrt[4]{8}$
- b) $\frac{\sqrt[3]{81}}{\sqrt[3]{3}}$
In the design of a new smartphone chip, one of the connections has a length given by the product of two radical components. Calculate the exact value of this length by…
In the design of a new smartphone chip, one of the connections has a length given by the product of two radical components. Calculate the exact value of this length by simplifying the following product and expressing it under a single radical:
$\sqrt[3]{a^2} \times \sqrt[4]{a^3}$
In a graphic design studio, work is being done on a logo that uses a spiral based on rectangles. One of the critical segments has a length $L$ defined by the operation…
In a graphic design studio, work is being done on a logo that uses a spiral based on rectangles. One of the critical segments has a length $L$ defined by the operation between the following radicals with different indices. Calculate its exact value and simplify it:
$$L = \frac{\sqrt[4]{32} \times \sqrt[3]{16}}{\sqrt[6]{2}}$$The root of a root
Apply the properties of radicals to reduce to a single root and simplify the final result: $\sqrt[3]{\sqrt{64x^{12}}}$
Apply the properties of radicals to reduce to a single root and simplify the final result:
$\sqrt[3]{\sqrt{64x^{12}}}$
Reduce the following expression to a single radical as simple as possible, applying the properties of a root of a root and the extraction of factors:…
Reduce the following expression to a single radical as simple as possible, applying the properties of a root of a root and the extraction of factors:
$\sqrt{\sqrt[3]{64x^8}}$
Simplify the following expression with nested radicals to convert it into a power with a fractional exponent with base $a$: $$\sqrt[3]{a^2 \times \sqrt{a \times…
Simplify the following expression with nested radicals to convert it into a power with a fractional exponent with base $a$:
$$\sqrt[3]{a^2 \times \sqrt{a \times \sqrt[4]{a^3}}}$$Products with binomials
To multiply expressions with radicals, use the distributive property and the special products, just as with polynomials.
A technology company is designing a new smartphone model. The screen is rectangular and its exact dimensions are given by the following radicals: the base measures…
A technology company is designing a new smartphone model. The screen is rectangular and its exact dimensions are given by the following radicals: the base measures $\sqrt{12}$ cm and the height measures $\sqrt{3}$ cm. Calculate the area of the screen, expressing the result in simplified form.
Perform the following combined operation with radicals, applying the distributive property and simplifying like terms: $(\sqrt{3} + 2) \times (2\sqrt{3} - 5)$
Perform the following combined operation with radicals, applying the distributive property and simplifying like terms:
$(\sqrt{3} + 2) \times (2\sqrt{3} - 5)$
Calculate the area of a square plaza whose side measures $(2 + \sqrt{5})$ meters. Express the result in exact form, simplifying any radicals that appear when expanding…
Calculate the area of a square plaza whose side measures $(2 + \sqrt{5})$ meters. Express the result in exact form, simplifying any radicals that appear when expanding the binomial.
Rationalizing a monomial denominator
Rationalise the following fractions so that no radical remains in the denominator. Remember to simplify the final result if possible: a) $\frac{10}{\sqrt{2}}$ b)…
Rationalise the following fractions so that no radical remains in the denominator. Remember to simplify the final result if possible:
- a) $\frac{10}{\sqrt{2}}$
- b) $\frac{3}{\sqrt[3]{5}}$
Rationalise the following expressions to eliminate the radicals from the denominator and simplify the final result: a) $\dfrac{6}{\sqrt[3]{9}}$ b) $\dfrac{10}{\sqrt{5}}$
Rationalise the following expressions to eliminate the radicals from the denominator and simplify the final result:
- a) $\dfrac{6}{\sqrt[3]{9}}$
- b) $\dfrac{10}{\sqrt{5}}$
An interior decorator wants to place a wooden moulding around a large square mirror that has an area of $20 \text{ m}^2$. Express the perimeter of the mirror in…
An interior decorator wants to place a wooden moulding around a large square mirror that has an area of $20 \text{ m}^2$. Express the perimeter of the mirror in simplified radical form (extract factors if necessary).
Rationalizing a binomial denominator (conjugate)
An architect needs to calculate the pressure exerted by a structure on the ground. After completing the initial calculations, the resulting expression is as follows.…
An architect needs to calculate the pressure exerted by a structure on the ground. After completing the initial calculations, the resulting expression is as follows. Rationalise it using the conjugate of the denominator and simplify it as much as possible:
$\dfrac{4}{\sqrt{7} - \sqrt{3}}$
Rationalise and simplify the following fraction. You must work out the numerator after rationalising to obtain the simplest possible expression: $$\frac{2\sqrt{6} -…
Rationalise and simplify the following fraction. You must work out the numerator after rationalising to obtain the simplest possible expression:
$$\frac{2\sqrt{6} - 3\sqrt{2}}{2\sqrt{3} + \sqrt{2}}$$Denominator with three radicals
When the denominator has three terms, such as $\sqrt2+\sqrt3-\sqrt5$, you group two of them so that the denominator looks like a binomial $A-B$ and rationalize twice.
Rationalise the following expression. Note that, as there are three square roots in the denominator, you may need to multiply by the conjugate more than once:…
Rationalise the following expression. Note that, as there are three square roots in the denominator, you may need to multiply by the conjugate more than once:
$$\frac{4}{\sqrt{2} + \sqrt{3} - \sqrt{5}}$$Rationalise the following expression and simplify the result by extracting all possible factors from the radicals: $$\frac{\sqrt{2}}{\sqrt{2} + \sqrt{3} - \sqrt{5}}$$ Is…
Rationalise the following expression and simplify the result by extracting all possible factors from the radicals:
$$\frac{\sqrt{2}}{\sqrt{2} + \sqrt{3} - \sqrt{5}}$$Is the result a rational or irrational number? Justify your answer by analysing the structure of the number obtained.
For the last exercise: after rationalizing, you get the sum of a whole number and radicals that are not like radicals, such as $\sqrt6$ and $\sqrt{15}$. Analyze that structure to decide whether the result is rational or irrational.
Putting it all together and applications
Simplify the following combined expression as much as possible, extracting factors from the radicals and rationalising any terms necessary to group the numerical part:…
Simplify the following combined expression as much as possible, extracting factors from the radicals and rationalising any terms necessary to group the numerical part:
$$3\sqrt{175} - \frac{5}{\sqrt{7}} + \sqrt[4]{441} - 2\sqrt{112}$$An architect is designing a triangular skylight for a new shopping center. The design requires the base of the skylight to be an equilateral triangle whose height is…
An architect is designing a triangular skylight for a new shopping center. The design requires the base of the skylight to be an equilateral triangle whose height is exactly $H = \sqrt{18} + \sqrt{6}$ meters. Calculate the exact value of the area of the skylight, expressing the result as a simplified radical in $m^2$.
A metal structure in the shape of a rectangular prism is to be built, whose dimensions (width, length and height) are given by the following expressions in meters:…
A metal structure in the shape of a rectangular prism is to be built, whose dimensions (width, length and height) are given by the following expressions in meters:
-
$a = \sqrt{2} + \sqrt{3}$
-
$b = \sqrt{2} - \sqrt{3} + \sqrt{6}$
-
$c = \sqrt{6}$
Calculate the total volume of the structure. The result must be a real number expressed in exact form (with radicals if necessary).