Advertisements
Advertisements
Show that: `tan "A"/(1 + tan^2 "A")^2 + cot "A"/(1 + cot^2 "A")^2 = sin"A" xx cos"A"`
Concept: undefined >> undefined
If x = `θ/360` × 2πr then what is x in the formula?
Concept: undefined >> undefined
Advertisements
In the given figure, a rectangle ABCD is inscribed inside a semi-circle of radius 10 cm. Using the dimensions given in the figure, determine the area of the shaded region.

Concept: undefined >> undefined
The perimeter of an arc of radius 4.2 cm is 12.8 cm. Determine the angle subtended by the arc at the centre of circle.
Concept: undefined >> undefined
In an isosceles triangle PQR, the length of equal sides PQ and PR is 13 cm and base QR is 10 cm. Find the length of perpendicular bisector drawn from vertex P to side QR.
Concept: undefined >> undefined
In the adjoining figure, a tangent is drawn to a circle of radius 4 cm and centre C, at the point S. Find the length of the tangent ST, if CT = 10 cm.

Concept: undefined >> undefined
If cot θ = `40/9`, find the values of cosec θ and sinθ,
We have, 1 + cot2θ = cosec2θ
1 + `square` = cosec2θ
1 + `square` = cosec2θ
`(square + square)/square` = cosec2θ
`square/square` = cosec2θ ......[Taking root on the both side]
cosec θ = `41/9`
and sin θ = `1/("cosec" θ)`
sin θ = `1/square`
∴ sin θ = `9/41`
The value is cosec θ = `41/9`, and sin θ = `9/41`
Concept: undefined >> undefined
In an equilateral triangle PQR, prove that PS2 = 3(QS)2.

Concept: undefined >> undefined
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: undefined >> undefined
Eliminate θ if x = r cosθ and y = r sinθ.
Concept: undefined >> undefined
`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: undefined >> undefined
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: undefined >> undefined
In the following figure, m(arc PMQ) = 130o, find ∠PQS.

Concept: undefined >> undefined
In the following figure, secants containing chords RS and PQ of a circle intersects each other in point A in the exterior of a circle if m(arc PCR) = 26°, m(arc QDS) = 48°, then find:
(i) m∠PQR
(ii) m∠SPQ
(iii) m∠RAQ

Concept: undefined >> undefined
Write the equation of the line passing through A(–3, 4) and B(4, 5) in the form of ax + by + c = 0
Concept: undefined >> undefined
Show that points A(–4, –7), B(–1, 2), C(8, 5) and D(5, –4) are vertices of a rhombus ABCD.
Concept: undefined >> undefined
If \[\sin\theta = \frac{7}{25}\], find the values of cosθ and tanθ.
Concept: undefined >> undefined
If \[\tan \theta = \frac{3}{4}\], find the values of secθ and cosθ
Concept: undefined >> undefined
If \[\cot\theta = \frac{40}{9}\], find the values of cosecθ and sinθ.
Concept: undefined >> undefined
If 5 secθ – 12 cosecθ = 0, find the values of secθ, cosθ, and sinθ.
Concept: undefined >> undefined
