Final answer:
To prove the given identity, we can simplify the left side by using double-angle identities and combining like terms. We can then rewrite the expression using the identity tan(x) = sin(x)/cos(x).
Step-by-step explanation:
To prove the given identity: sinx+ sin2x/1 + coax+ cos2x= tanx
Let's start by simplifying the left side of the equation:
sin(x) + (sin(2x))/(1 + cos(x) + cos(2x))
Next, we can use the double-angle identities for sine and cosine:
sin(x) + 2sin(x)cos(x)/(1 + cos(x) + 2cos^2(x) - 1)
Now, we can combine like terms:
sin(x) + 2sin(x)cos(x)/(cos(x) + 2cos^2(x))
Finally, we can use the identity tan(x) = sin(x)/cos(x) to rewrite the expression:
tan(x)