Notes: `sin(x)cos(x)` Use a double angle formula to rewrite the expression.

Monday, 7 March 2016

You need to use the double angle formula to re-write the expression, such that:

$\displaystyle{\sin{{2}}}{x}={2}{\sin{{x}}}\cdot{\cos{{x}}}\Rightarrow{\sin{{x}}}\cdot{\cos{{x}}}=\frac{{{\sin{{2}}}{x}}}{{2}}$

Hence, using the double angle formula to re-write the expression yields $\displaystyle{\sin{{x}}}\cdot{\cos{{x}}}=\frac{{{\sin{{2}}}{x}}}{{2}}.$

You need to use the double angle formula to re-write the expression, such that:

$\displaystyle{\sin{{2}}}{x}={2}{\sin{{x}}}\cdot{\cos{{x}}}\Rightarrow{\sin{{x}}}\cdot{\cos{{x}}}=\frac{{{\sin{{2}}}{x}}}{{2}}$

Hence, using the double angle formula to re-write the expression yields $\displaystyle{\sin{{x}}}\cdot{\cos{{x}}}=\frac{{{\sin{{2}}}{x}}}{{2}}.$

Notes