Respuesta :

Answer:

  [tex]cos(a-b) = \frac{117}{125}[/tex]

Step-by-step explanation:

Explanation

Given that

 [tex]sina = \frac{7}{25} , cos a = \frac{24}{25} , sinb =\frac{3}{5} and cosb =\frac{4}{5}[/tex]

Cos(a-b) = cosa cosb + sina sinb

             [tex]cos(a-b) = \frac{24}{25} \frac{4}{5} +\frac{7}{25} \frac{3}{5}[/tex]

            [tex]cos(a-b) = \frac{96}{125} +\frac{21}{125} = \frac{117}{125}[/tex]

Final answer:-

 [tex]cos(a-b) = \frac{117}{125}[/tex]