Given that cos(30°) = cos(45°)cos(15°) + sin(45°)sin(15°), it follows that cos(30°) =

Answer:[tex]cos(30\°) = cos(45\°-15\°)[/tex]Step-by-step explanation:To solve this problem you must know the formula of subtraction of angles for the function cosx.The formula is:[tex]cos(h-d) = cos(h)cos(d) + sin(h)sin(d)[/tex]We can write 30° as: 45° - 15°Then:[tex]cos(30\°) = cos(45\°-15\°)[/tex]Using the formula for subtraction of angles we have:[tex]cos(45\°-15\°) = cos(45\°)cos(15\°) + sin(45\°)sin(15\°)[/tex]Notice that we have achieved the expression shown in the statementFinally:[tex]cos(30\°) = cos(45\°-15\°)[/tex]