Find the value of sin 2A 1. CosA = 3/5 2. SinA = 12/13 3. TanA= 16/63?
Sin2a = 2sinAcosA
tan a= sina/cosa
or tan a= p/b = 16/63
so we get p =16 b= 63
we need to find the third side h so we use pythagorous theorem
c= √p^2+b^2
c= √16^2+63 ^2= √4225 = 65
so we got hypotaneious side dude
now
sin a = p/h which means
sin a = 16/65
and cos a= b/h which means
cos a = 63/65
now we need to calculate sin2a
sin2 a = 2sin a cos a
now we can directly put our values
sin2 a = 2x16/65 x63/65 = 0.47 approx dude have any doubt ask in comment box
sin 2 a = 0.47
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Find the value of sin 2A 1. CosA = 3/5 2. SinA = 12/13 3. TanA= 16/63?
1. CosA = 3/5
To find the value of sin 2A, we need to use trigonometric identities. One of the most commonly used identities is the double-angle identity for sine, which states:
sin 2A = 2 sin A cos A
Given that cos A = 3/5, we can find sin A using the Pythagorean identity, which states:
sin^2 A + cos^2 A = 1
Substituting the value of cos A, we have:
sin^2 A + (3/5)^2 = 1
sin^2 A + 9/25 = 1
sin^2 A = 1 - 9/25
sin^2 A = 16/25
Taking the square root of both sides, we get:
sin A = ±4/5
Since we are given that sin A is positive, we have sin A = 4/5.
Now, substituting the values of sin A and cos A into the double-angle identity for sine, we have:
sin 2A = 2(4/5)(3/5)
sin 2A = 24/25
Therefore, the value of sin 2A is 24/25.
2. SinA = 12/13
Similar to the previous case, we can use the double-angle identity for sine:
sin 2A = 2 sin A cos A
Given that sin A = 12/13, we need to find the value of cos A. Using the Pythagorean identity:
sin^2 A + cos^2 A = 1
Substituting the value of sin A, we have:
(12/13)^2 + cos^2 A = 1
144/169 + cos^2 A = 1
cos^2 A = 1 - 144/169
cos^2 A = 25/169
Taking the square root of both sides, we get:
cos A = ±5/13
Since we are given that cos A is positive, we have cos A = 5/13.
Now, substituting the values of sin A and cos A into the double-angle identity for sine, we have:
sin 2A = 2(12/13)(5/13)
sin 2A = 120/169
Therefore, the value of sin 2A is 120/169.
3. TanA = 16/63
To find the value of sin 2A, we need to use the double-angle identity for sine:
sin 2A = 2 sin A cos A
Given that tan A = 16/63, we can find the values of sin A and cos A using the definitions of tangent:
tan A = sin A / cos A
Substituting the value of tan A, we have:
16/63 = sin A / cos A
16 cos A = 63 sin A
Using the Pythagorean identity:
sin^2 A + cos^2 A = 1
Substituting the value of cos A, we have:
sin^2 A + (63/16)^2 sin^2 A = 1
(1 + (63/16)^2) sin^2 A = 1
(1 +
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