Answer: [tex]\dfrac{1}{\sqrt{2}}[/tex]
Step-by-step explanation:
The value of [tex]\cos 45^{\circ}[/tex] is the fixed value i.e. [tex]\frac{1}{\sqrt{2}}[/tex]
The values of cosine changes from a maximum at [tex]0^{\circ}[/tex] to a minimum at [tex]180^{\circ}[/tex]
for example, [tex]\cos 0^{\circ}=1, \quad \cos 90^{\circ}=0,\quad \cos 180^{\circ}=-1[/tex]
