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Show that, cotθ + tanθ = cosecθ × secθ
Solution :
L.H.S. = cotθ + tanθ
= `cosθ/sinθ + sinθ/cosθ`
= `(square + square)/(sinθ xx cosθ)`
= `1/(sinθ xx cosθ)` ............... `square`
= `1/sinθ xx 1/square`
= cosecθ × secθ
L.H.S. = R.H.S
∴ cotθ + tanθ = cosecθ × secθ
Concept: Trigonometric Identities (Square Relations)
Eliminate θ if x = r cosθ and y = r sinθ.
Concept: Trigonometric Identities (Square Relations)
`1/sin^2θ - 1/cos^2θ - 1/tan^2θ - 1/cot^2θ - 1/sec^2θ - 1/("cosec"^2θ) = -3`, then find the value of θ.
Concept: Trigonometric Identities (Square Relations)
Find the value of sin2θ + cos2θ

Solution:
In Δ ABC, ∠ABC = 90°, ∠C = θ°
AB2 + BC2 = `square` .....(Pythagoras theorem)
Divide both sides by AC2
`"AB"^2/"AC"^2 + "BC"^2/"AC"^2 = "AC"^2/"AC"^2`
∴ `("AB"^2/"AC"^2) + ("BC"^2/"AC"^2) = 1`
But `"AB"/"AC" = square and "BC"/"AC" = square`
∴ `sin^2 theta + cos^2 theta = square`
Concept: Trigonometric Identities (Square Relations)
The radius of a circle is 7 cm. find the circumference of the circle.
Concept: Circumference of a Circle
In figure, ΔABC is an isosceles triangle with perimeter 44 cm. The base BC is of length 12 cm. Side AB and side AC are congruent. A circle touches the three sides as shown in the figure below. Find the length of the tangent segment from A to the circle.

Concept: Circumference of a Circle
The radii of ends of a frustum are 14 cm and 6 cm respectively and its height is 6 cm. Find its volume \[\pi\] = 3.14)
Concept: Frustum of a Cone
The circumferences of circular faces of a frustum are 132 cm and 88 cm and its height is 24 cm. To find the curved surface area of the frustum complete the following activity.( \[\pi = \frac{22}{7}\])

Concept: Frustum of a Cone
In the given figure,
\[\square\] PQRS is a rectangle. If PQ = 14 cm, QR = 21 cm, find the areas of the parts x, y, and z.

Concept: Circumference of a Circle
Concept: Circumference of a Circle
Choose the correct alternative answer for the following question.
The curved surface area of a cylinder is 440 cm 2 and its radius is 5 cm. Find its height.
Concept: Circumference of a Circle
Choose the correct alternative answer for the following question.
Concept: Circumference of a Circle
Choose the correct alternative answer for the following question.
Concept: Circumference of a Circle
The area of a sector of a circle of 6 cm radius is 15 π sq. cm. Find the measure of the arc and the length of the arc corresponding to the sector.
Concept: Length of an Arc

In the given figure, seg AB is a chord of a circle with centre P. If PA = 8 cm and distance of chord AB from the centre P is 4 cm, find the area of the shaded portion. ( \[\pi\] = 3.14, \[\sqrt{3}\]= 1.73 )
Concept: Length of an Arc
In Δ ABC, if ∠ A = 65° ; ∠ B = 40° then find the measure of ∠ C.
Concept: Length of an Arc
Length of a rectangular tank is twice its breadth. If the
depth of the tank is 3 m and area of its four walls is 108 m2, find the
length of the tank.
Concept: Length of an Arc
Diagonal of a square is 20 cm. Find the length and perimeter of the square.
Concept: Circumference of a Circle
Find the length of an arc if measure of the arc is 90° and its radius
is 14 cm.
Concept: Length of an Arc
Measure of an arc of a sector of a circle is 900 and its radius is 7cm. Find the perimeter of the sector.
(A) 44 cm (B) 25 cm (C) 36 cm (D) 56 cm
Concept: Length of an Arc
