Question

7=√[5²+12²+2(5)(12) cos x]​

Answer 1

Step-by-step explanation:

7^2=5^+12^2+2×5×12×cosx

49=25+144+120cosx

49=169+120cosx

49-169=120cosx

-120=120cosx

-120/120=cosx

-1=cosx

x=π