Math, asked by devsaini1234, 1 year ago

the angle of elevation of the top of a tower from two points at distance A and B metres from the base and in the same straight line with it are complementary prove that the height of the tower is root ab metre

Answers

Answered by saltywhitehorse
476

Answer:

Step-by-step explanation:

Figure show in attachment

Given,

Height of the tower = h

Distance between the tower and point one = BC = A meter

Distance between the tower and point one = BD = B meter

The ∠ACB +∠ADB = 90° (complementary angle) and ∠ABC=∠ABD=90°

Proved that h=\sqrt{AB}

Consider \angle{ACB}=\theta

So \angle{ADB}=(90^{\circ}-\theta)

In right-angle triangle ABC

tan\theta=\frac{AB}{BC}\\\\tan\theta=\frac{h}{A}...........equation-1

In right-angle triangle ABD

tan(90^{\circ}-\theta)=\frac{AB}{BD}\\\\tan(90^{\circ}-\theta)=\frac{h}{B}...........equation-2

Now multiplying equation 1 with equation 2 we get

tan\theta\times{cot}\theta=\frac{h}{A}\times\frac{h}{B}\\\\tan\theta\times\frac{1}{tan\theta}=\frac{h^{2}}{AB}\\\\1=\frac{h^{2}}{AB}\\\\h^{2}=AB\\\\h=\sqrt{AB}

Hence RHS=LHS (proved)

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Answered by khushi0851
223

Here is your answer user.

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