Let AB be the building of height ‘h’ and BC be the hoarding pole of height 12 m. Let θ be the angle of elevation as seen by the person at a distance of ‘x’ m and ‘x + 4 √ 3‘ m. In Δ DAB, tan θ = h/x (i) In Δ EAC, tan θ = (h + 12)/ (x + 4 √ 3) (ii) From (i) and (ii) h/x = (h + 12)/ (x + 4 √ 3) ⇒ hx + 4 √ 3h = hx +12x ⇒ h/x = 12/ 4 √ 3 = √ 3 ⇒ tan θ = h/x = √ 3 = tan 60° ⇒ θ = 60°
Which of the following options is INCORRECT?
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