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Please help with these 3 questions-

Please help with these 3 questions--example-1

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Answer:

See attachments.

Explanation:

Trigonometric ratios are mathematical expressions defining the relationships between the angles and sides of a right-angled triangle.

The primary trigonometric ratios are:


\boxed{\begin{array}{l}\underline{\sf Trigonometric\;ratios}\\\\\sf \sin(\theta)=(O)/(H)\qquad\cos(\theta)=(A)/(H)\qquad\tan(\theta)=(O)/(A)\\\\\textsf{where:}\\\phantom{ww}\bullet\;\textsf{$\theta$ is the angle.}\\\phantom{ww}\bullet\;\textsf{O is the side opposite the angle.}\\\phantom{ww}\bullet\;\textsf{A is the side adjacent the angle.}\\\phantom{ww}\bullet\;\textsf{H is the hypotenuse (the side opposite the right angle).}\\\\\end{array}}


\hrulefill

Question 4

Given:


\sin(A)=(1)/(2)

The provided sine ratio implies that the side opposite angle A is one unit in length, and the hypotenuse is 2 units.

In a right triangle, the side opposite the right angle is the hypotenuse.

In right triangle ABC, let ∠C = 90°, which makes side c the hypotenuse, and sides a and b the legs. So, a = 1 and c = 2.

To find the length of leg b (the side adjacent to angle A), substitute a = 1 and c = 2 into the Pythagorean Theorem:


\begin{aligned}a^2+b^2&=c^2\\1^2+b^2&=2^2\\1+b^2&=4\\b^2&=3\\b&=√(3)\end{aligned}

Therefore, the length of leg b is b = √3.

We can find the measure of angle A by solving using the given ratio:


\sin(A)=(1)/(2)\implies A=\arcsin\left((1)/(2)\right)=30^(\circ)

Since the interior angles of a triangle sum to 180°, then:


B=180^(\circ)-A-C


B=180^(\circ)-30^(\circ)-90^(\circ)


B=60^(\circ)

Therefore:

  • a = 1
  • b = √3
  • c = 2
  • A = 30°
  • B = 60°
  • C = 90°

These values allow us to sketch the right triangle based on the determined lengths and angles (see attachment 1).


\hrulefill

Question 5

Given:


\cos(B)=\frac35

The provided cosine ratio implies that the side adjacent angle B is 3 units in length, and the hypotenuse is 5 units.

In a right triangle, the side opposite the right angle is the hypotenuse.

In right triangle ABC, let ∠C = 90°, which makes side c the hypotenuse, and sides a and b the legs. So, a = 3 and c = 5.

To find the length of leg b (the side adjacent to angle A), substitute a = 3 and c = 5 into the Pythagorean Theorem:


\begin{aligned}a^2+b^2&=c^2\\3^2+b^2&=5^2\\9+b^2&=25\\b^2&=16\\b&=4\end{aligned}

Therefore, the length of leg b is b = 4.

We can find the measure of angle B by solving using the given ratio:


\cos(B)=(3)/(5)\implies B=\arccos\left((3)/(5)\right)=53.1^(\circ)

Since the interior angles of a triangle sum to 180°, then:


A=180^(\circ)-B-C


A=180^(\circ)-53.1^(\circ)-90^(\circ)


A=36.9^(\circ)

Therefore:

  • a = 3
  • b = 4
  • c = 5
  • A = 36.9°
  • B = 53.1°
  • C = 90°

These values allow us to sketch the right triangle based on the determined lengths and angles (see attachment 2).


\hrulefill

Question 6

Given:


\tan(B)=\frac67

The provided tangent ratio implies that the side opposite angle B is 6 units in length, and the side adjacent angle B is 7 units.

In a right triangle, the side opposite the right angle is the hypotenuse.

In right triangle ABC, let ∠C = 90°, which makes side c the hypotenuse, and sides a and b the legs. So, a = 7 and b = 6.

To find the length of the hypotenuse, substitute a = 7 and b = 6 into the Pythagorean Theorem, and solve for c:


\begin{aligned}a^2+b^2&=c^2\\7^2+6^2&=c^2\\49+36&=c^2\\85&=c^2\\c&=√(85)\end{aligned}

Therefore, the length of the hypotenuse is c = √(85).

We can find the measure of angle B by solving using the given ratio:


\tan(B)=\frac67\implies B=\arctan\left(\frac67\right)=40.6^(\circ)

Since the interior angles of a triangle sum to 180°, then:


A=180^(\circ)-B-C


A=180^(\circ)-40.6^(\circ)-90^(\circ)


A=49.4^(\circ)

Therefore:

  • a = 7
  • b = 6
  • c = √(85)
  • A = 49.4°
  • B = 40.6°
  • C = 90°

These values allow us to sketch the right triangle based on the determined lengths and angles (see attachment 3).

Please help with these 3 questions--example-1
Please help with these 3 questions--example-2
Please help with these 3 questions--example-3
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