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
In right angled triangle ΔABC at B, ∠A = ∠C. Find the values of Sin A cos C + Cos A Sin C
If tan θ =`15/ 8 `, find the values of all T-ratios of θ.
If 3 cot `theta = 2, `show that `((4 sin theta - 4 cos theta))/((2 sin theta + 6 cos theta ))=1/3`
Evaluate:
`(sin^2 30^0 + 4 cot^2 45^0-sec^2 60^0)(cosec^2 45^0 sec^2 30^0)`
If A = 600 and B = 300, verify that:
(ii) cos (A – B) = cos A cos B + sin A sin B
sin20° = cos ______°
Given: sec A = `( 29 )/(21), "evaluate : sin A" - 1/tan "A"`
In triangle ABC; ∠ABC = 90°, ∠CAB = x°, tan x° = `(3)/(4)` and BC = 15 cm. Find the measures of AB and AC.
If 3 cos A = 4 sin A, find the value of :
(i) cos A(ii) 3 - cot2 A + cosec2A.
In the given figure, AD is the median on BC from A. If AD = 8 cm and BC = 12 cm, find the value of cos y