FizeauV
2020-10-26
Answered

What is the value $\mathrm{cos}\left({72}^{\circ}\right)$ ? Write your answer in decimals.

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Demi-Leigh Barrera

Answered 2020-10-27
Author has **97** answers

The formula:

Substitute the given angle:

asked 2022-07-31

The following conclusion is true. Is the argument valid or invalid?

A scalene triangle has a largest angle.

A scalene triangle has a longest side.

The largest angle in a scalene triangle is opposite the longest side.

Is this argument valid or invalid?

Valid or Invalid

A scalene triangle has a largest angle.

A scalene triangle has a longest side.

The largest angle in a scalene triangle is opposite the longest side.

Is this argument valid or invalid?

Valid or Invalid

asked 2022-06-18

Problem: $O$ is the circumcenter of $\mathrm{\u25b3}ABC$, which is not a right triangle.

$\frac{|AB\cdot CO|}{|AC\cdot BO|}=\frac{|AB\cdot BO|}{|AC\cdot CO|}=3$.

Find $\mathrm{tan}A$. Here $AB\cdot CO$ represents the dot product of vector $\overrightarrow{AB}$ and $\overrightarrow{CO}$

$\frac{|AB\cdot CO|}{|AC\cdot BO|}=\frac{|AB\cdot BO|}{|AC\cdot CO|}=3$.

Find $\mathrm{tan}A$. Here $AB\cdot CO$ represents the dot product of vector $\overrightarrow{AB}$ and $\overrightarrow{CO}$

asked 2021-01-02

In triangle ABC with sides a, b, and c the Law of Sines states that

asked 2021-11-26

Use the Law of Cosines to solve the triangles. Round lengths to the nearest tenth and angle measures to the
nearest degree. PLEASE solve both of these triangles. Thank you!

asked 2020-12-06

if $\mathrm{\angle}c=\mathrm{\angle}b{\textstyle \phantom{\rule{1em}{0ex}}}\text{and}{\textstyle \phantom{\rule{1em}{0ex}}}\mathrm{\angle}a=4\mathrm{\angle}b$ , find the value of each angle.

asked 2021-10-14

One of the largest issues in ancient mathematics was accuracy-nobody had calculators that went out ten decimal places, and accuracy generally got worse as the numbers got larger. The famous Eratosthenes experiment, that can be found at relied on the fact known to Thales and others that a beam of parallels cut by a transverse straight line determines equal measure for the corresponding angles.

Given two similar triangles, one with small measurements that can be accurately determined, and the other with large measurements, but at least one is known with accuracy, can the other two measurements be deduced? Explain and give an example. The similarity of triangles gives rise to trigonometry.

How could we understand that the right triangles of trigonometry with a hypotenuse of measure 1 represent all possible right triangles? Ultimately, the similarity of triangles is the basis for proportions between sides of two triangles, and these proportions allow for the calculations of which we are speaking here. The similarity of triangles is the foundation of trigonometry.

Given two similar triangles, one with small measurements that can be accurately determined, and the other with large measurements, but at least one is known with accuracy, can the other two measurements be deduced? Explain and give an example. The similarity of triangles gives rise to trigonometry.

How could we understand that the right triangles of trigonometry with a hypotenuse of measure 1 represent all possible right triangles? Ultimately, the similarity of triangles is the basis for proportions between sides of two triangles, and these proportions allow for the calculations of which we are speaking here. The similarity of triangles is the foundation of trigonometry.

asked 2021-09-09

Given a right triangle, where one cathetus is $\stackrel{\u2015}{A}=51$ m and the second cathetus is $\stackrel{\u2015}{B}=39$ m. Find the hypothenuse $\left(\stackrel{\u2015}{C}\right)$ and the angle opposite to $\stackrel{\u2015}{B}\left(\mathrm{\angle}a\right)$