Demonstration of the duplication formula
Open answerStarting from the formula sin(a+b) = sin(a) * cos(b) + cos(a) * sin(b), prove that sin(2a) = 2 * sin(a) * cos(a). Set out your proof in detail, explaining each step.
Starting from the formula sin(a+b) = sin(a) * cos(b) + cos(a) * sin(b), prove that sin(2a) = 2 * sin(a) * cos(a). Set out your proof in detail, explaining each step.