Question

2 cos^2 13П/24 cos^2 23П/24​

Answer 1

$2Cos^{2} frac{13pi }{24}Cos^{2} frac{23pi }{24} =2Cos^{2}(frac{pi }{2}+frac{pi }{24})Cos^{2}(pi-frac{pi }{24})=2Sin^{2}frac{pi }{24}Cos^{2}frac{pi }{24}=0,5Sin^{2}frac{pi }{12}$