If a+b+c=pi show that cos a/2+cos b/2 cos c/2= 4cos (b+c/4)cos (c+a/4)cos(a+b/4)

What is the prime factorization of 23 ?me with this question

Jamie went to home depot.she bought 25 bags of soil that cost $9 per bag.she bought 15 pots at $8 each,and she bought 23 bags of pebbles at $15 each.she used a coupon that gave her $5 off for every 100 dollars she spent.how much did jame pay at the end?

Why is studying fractions important