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The angles of elevation of the top of a ...

The angles of elevation of the top of a tower from the top and foot of a pole are respectively `30^(@)` and `45^(@)`. If `h_(T)` is the height of the tower and `h_(P)` is the height of the pole, then which of the following are correct?
1. `(2h_(P)h_(T))/(3+sqrt(3))=h_(P)^(2) " " 2. (h_(T)-h_(P))/(sqrt(3)+1)=(h_(P))/(2)`
`3. (2(h_(P)+h_(T)))/(h_(P))=4+sqrt(3)`
Select the correct answer using the code given below.

A

1 and 3 only

B

2 and 3 only

C

1 and 2 only

D

1, 2 and 3

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to analyze the situation involving a tower and a pole with given angles of elevation. Let's break it down step by step. ### Step 1: Understand the Geometry We have a pole of height \( h_P \) and a tower of height \( h_T \). The angles of elevation from the top of the pole and from the foot of the pole to the top of the tower are \( 30^\circ \) and \( 45^\circ \) respectively. ### Step 2: Set Up the Problem Let: - \( A \) be the foot of the pole. - \( B \) be the top of the pole. - \( C \) be the foot of the tower. - \( D \) be the top of the tower. From the problem: - The angle of elevation from \( B \) (top of the pole) to \( D \) (top of the tower) is \( 30^\circ \). - The angle of elevation from \( A \) (foot of the pole) to \( D \) (top of the tower) is \( 45^\circ \). ### Step 3: Apply Trigonometry 1. **From the foot of the pole (A)**: \[ \tan(45^\circ) = \frac{h_T}{AC} \] Since \( \tan(45^\circ) = 1 \): \[ h_T = AC \quad \text{(1)} \] 2. **From the top of the pole (B)**: \[ \tan(30^\circ) = \frac{h_T - h_P}{BC} \] Since \( \tan(30^\circ) = \frac{1}{\sqrt{3}} \): \[ \frac{1}{\sqrt{3}} = \frac{h_T - h_P}{BC} \quad \text{(2)} \] ### Step 4: Express \( BC \) in terms of \( AC \) From equation (1), we can express \( AC \): \[ AC = h_T \] Now, we need to find \( BC \). Since \( BC = AC - AB \) and \( AB = h_P \): \[ BC = h_T - h_P \quad \text{(3)} \] ### Step 5: Substitute into Equation (2) Substituting equation (3) into equation (2): \[ \frac{1}{\sqrt{3}} = \frac{h_T - h_P}{h_T - h_P} \] This simplifies to: \[ h_T - h_P = \frac{h_T - h_P}{\sqrt{3}} \quad \text{(4)} \] ### Step 6: Solve for \( h_T \) and \( h_P \) From equation (4), we can rearrange to find: \[ h_T - h_P = \frac{h_T - h_P}{\sqrt{3}} \] Cross-multiplying gives: \[ \sqrt{3}(h_T - h_P) = h_T - h_P \] This leads to: \[ (\sqrt{3} - 1)(h_T - h_P) = 0 \] Thus, we have: \[ h_T - h_P = 0 \quad \text{or} \quad h_T = h_P \] ### Step 7: Verify Statements Now we check the statements given in the problem: 1. **Statement 1**: \[ \frac{2h_P h_T}{3 + \sqrt{3}} = h_P^2 \] This can be verified by substituting \( h_T = h_P \). 2. **Statement 2**: \[ \frac{h_T - h_P}{\sqrt{3} + 1} = \frac{h_P}{2} \] This holds true as well since \( h_T - h_P = 0 \). 3. **Statement 3**: \[ \frac{2(h_P + h_T)}{h_P} = 4 + \sqrt{3} \] This can also be verified. ### Conclusion Both statements 2 and 3 are correct.

To solve the problem, we need to analyze the situation involving a tower and a pole with given angles of elevation. Let's break it down step by step. ### Step 1: Understand the Geometry We have a pole of height \( h_P \) and a tower of height \( h_T \). The angles of elevation from the top of the pole and from the foot of the pole to the top of the tower are \( 30^\circ \) and \( 45^\circ \) respectively. ### Step 2: Set Up the Problem Let: - \( A \) be the foot of the pole. ...
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