Q32 of 180 Page 3

Prove that:

L.H.S


We know that: sec2x – tan2x = 1.


Therefore, L.H.S


[Since, (a2 – b2) = (a + b(a – b)]




= tan x + sec x


= R.H.S


Hence, Proved.


More from this chapter

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30

A bag contains some red balls, some blue balls and some white balls. Out of which the number of blue balls is twice the number of white balls, and the probability of drawing a red ball is 1/2. Find the probability of drawing a white ball.

OR


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(i) A black card (ii) A red card


(iii) A red face card


 31

A solid is in the form of a cylinder with hemispherical ends. The total height of the solid is 19 cm, and the diameter of the cylinder is 7 cm. Find the volume and total surface area of the solid. (Use π = 22/7).

 33

A square is inscribed in a quadrant of a circle whose radius is 28cm as shown in the figure below. Find the area of the shaded region.



OR


The length of the minute hand of a clock is 10cm. Find the area swept by the minute hand of a clock from the time 6:10 to 7:05.


 34

From a point 200m above the lake, the angle of elevation of a stationary helicopter is 30˚, and the angle of depression of reflection of the helicopter in the lake is 45˚. Find the height of the helicopter.

OR


If the angles of elevation of a tower from two points at distances a and b, where a > b from its foot and in the same straight line from it are 30˚ and 60˚ respectively, the find the value of .