2cosx=2sin2x. Sin2x is an identity for 2sinxcos. So 2[2sinxcosx] gives you 4sinxcosx. 2cosx=4sinxcosx. Divide 2cosx on both sides and gives you 2sinx=0 and divide again, sinx=0. Sinx is 0 at 0 and 360 degrees, or pi and 2pi. So thats what x would be. 0,360,pi,2pi.
The solution for proving the identity is as follows:
sin(2A) = sin(A + A)
As sin(a + b) = sinacosb + sinbcosa,
<span>sin(A + A) = sinAcosA + sinAcosA
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<span>Therefore, sin(2A) = 2sinAcosA
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Answer:
f(g(5)) = 64
g(f(5)) = 28
Step-by-step explanation:
Given that f(x) = x^2 and g(x) = x+3
f(g(x) = f(x+3)
f(x+3) = (x+3)^2
f(g(x)) = (x+3)^2
f(g(5)) = (5+3)^2
f(g(5)) = 8^2
f(g(5)) = 64
b) g(f(x)) = g(x^2)
g(f(x)) = x^2 + 3
g(f(5)) = 5^2 +3
g(f(5)) = 25 + 3
g(f(5)) = 28
Hence the value of g(f(5)) is 28
Answer:
81
Step-by-step explanation:
Add all of the together to find how much they all equal. 27x3 = 81