Prove the identity
2sin^2x - 1 = sin^2x - cos^2x

Geometry: determine whether segment mn is parallel to segment kl. justify your answer. jm 6 mk 3 jn 8 nl 4

In the following situation, determine whether you are asked to determine the number of permutations or combinations. then do the calculation how many ways are there to pick a starting five from a basketball team of twelve members? a. permutation; ps - 2520 b. combination; 1c, - 792 c. combination: 2cs - 2520 d. permutation; ps - 95040

How do you find the circumfrance of a circle?