Advertisements
Advertisements
प्रश्न
If A = 300 , verify that:
(i) sin 2A = `(2 tan A)/(1+tan^2A)`
उत्तर
A = 300
⇒ 2A = 2 × 300 = 600
(i) sin 2A = sin `60^0 = sqrt(3)/2`
`(2 tan A)/(1+tan^2A)= (2 tan 30^0)/(1+ tan ^2 30^0) = (2xx(1/sqrt(3)))/(1+(1/sqrt(3))^2`=`((2/sqrt(3)))/(1+1/3) =((2/sqrt(3)))/(4/3)=(2/sqrt(3)) xx 3/4=sqrt(3)/2`
∴ sin 2A = `(2 tan A)/(1+tan^2 A)`
APPEARS IN
संबंधित प्रश्न
If 3tan θ 4 , show that `((4cos theta - sin theta ))/((4 cos theta + sin theta))=4/5`
If a right ΔABC , right-angled at B, if tan A=1 then verify that 2sin A . cos A = 1
If sin (A – B) = `1/2` and cos (A + B) = `1/2, 0^0 ≤ (A + B) ≤ 90^0` and A > B, then find A and B.
If sec A = `sqrt2`, find the value of :
`(3cos^2"A"+5tan^2"A")/(4tan^4"A"–sin^2"A")`
In triangle ABC, ∠B = 90° and tan A = 0.75. If AC = 30 cm, find the lengths of AB and BC.
In rectangle ABCD, diagonal BD = 26 cm and cotangent of angle ABD = 1.5. Find the area and the perimeter of the rectangle ABCD.
In ΔABC, ∠A = 90°. If AB = 5 units and AC = 12 units, find: sinB
In ΔABC, ∠A = 90°. If AB = 5 units and AC = 12 units, find: cos C
In a right-angled triangle PQR, ∠PQR = 90°, QS ⊥ PR and tan R =`(5)/(12)`, find the value of sin ∠PQS
Statement A (Assertion): For 0 < θ ≤ 90°, cosec θ – cot θ and cosec θ + cot θ are reciprocal of each other.
Statement R (Reason): cosec2 θ – cot2 θ = 1
