To prove that sin(2x/3) + cos^2(2x/3) = 1, we can first rewrite cos^2(2x/3) in terms of sin(2x/3) using the Pythagorean identity:
cos^2(2x/3) = 1 - sin^2(2x/3)
Then, substitute this expression back into the original equation:
sin(2x/3) + (1 - sin^2(2x/3)) = 1
Now we have:
sin(2x/3) + 1 - sin^2(2x/3) = 1
Rearranging terms, we get:
1 - sin^2(2x/3) + sin(2x/3) = 1
Since sin^2(2x/3) + sin(2x/3) = 1 (from the Pythagorean trigonometric identity), we have:
1 = 1
Therefore, we have proved that sin(2x/3) + cos^2(2x/3) = 1.
To prove that sin(2x/3) + cos^2(2x/3) = 1, we can first rewrite cos^2(2x/3) in terms of sin(2x/3) using the Pythagorean identity:
cos^2(2x/3) = 1 - sin^2(2x/3)
Then, substitute this expression back into the original equation:
sin(2x/3) + (1 - sin^2(2x/3)) = 1
Now we have:
sin(2x/3) + 1 - sin^2(2x/3) = 1
Rearranging terms, we get:
1 - sin^2(2x/3) + sin(2x/3) = 1
Since sin^2(2x/3) + sin(2x/3) = 1 (from the Pythagorean trigonometric identity), we have:
1 = 1
Therefore, we have proved that sin(2x/3) + cos^2(2x/3) = 1.