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Introduction to Trignometry & its Equation

An observer 1.5 metres tall is 20.5 metres away from a tower 22 metres high. Determine  the  angle  of  elevation  of  the  top  of  the  tower  from  the  eye  of  the observer.

Introduction to Trignometry & its Equation

 If 2sin²θ – cos²θ = 2, then find the value of θ.

Introduction to Trignometry & its Equation

 Simplify (1 + tan2θ) (1 – sinθ) (1 + sinθ)

Introduction to Trignometry & its Equation

A ladder 15 metres long just reaches the top of a vertical wall. If the ladder makes an angle of 60° with the wall, find the height of the wall.

Introduction to Trignometry & its Equation

Prove that sin⁶θ + cos⁶θ + 3sin²θ cos²θ = 1

Introduction to Trignometry & its Equation

Write ‘True’ or ‘False’ and justify your answer.

If the height of a tower and the distance of the point of observation from its foot, both, are increased by 10%, then the angle of elevation of its top remains unchanged.

Introduction to Trignometry & its Equation

Write ‘True’ or ‘False’ and justify your answer.

The angle of elevation of the top of a tower is 30°. If the height of the tower is doubled, then the angle of elevation of its top will also be doubled.

Introduction to Trignometry & its Equation

Write ‘True’ or ‘False’ and justify your answer.

If a man standing on a platform 3 metres above the surface of a lake observes a cloud and its reflection in the lake, then the angle of elevation of the cloud is equal to the angle of depression of its reflection.

Introduction to Trignometry & its Equation

Write ‘True’ or ‘False’ and justify your answer.

If the length of the shadow of a tower is increasing, then the angle of elevation of the sun is also increasing.

Introduction to Trignometry & its Equation

Write ‘True’ or ‘False’ and justify your answer.

If cosA + cos²A = 1, then sin²A + sin⁴A = 1.