If sin theta/2 = 1/2 (a+ 1/a ), prove that: cos theta = - 1/2 * (a ^ 2 +1/a^2)

1. what expression would be the same as 6x+x+0 2. find the prime factorization of 60 3. write the expression for 6 + x in words.

Write the contrapositive of the conditional statement. determine whether the contrapositive is true or false. if it is false, find a counterexample. a converse statement is formed by exchanging the hypothesis and conclusion of the conditional. a) a non-converse statement is not formed by exchanging the hypothesis and conclusion of the conditional. true b) a statement not formed by exchanging the hypothesis and conclusion of the conditional is a converse statement. false; an inverse statement is not formed by exchanging the hypothesis and conclusion of the conditional. c) a non-converse statement is formed by exchanging the hypothesis and conclusion of the conditional. false; an inverse statement is formed by negating both the hypothesis and conclusion of the conditional. d) a statement not formed by exchanging the hypothesis and conclusion of the conditional is not a converse statement. true

What is the missing reason in the proof? segment addition congruent segments theorem transitive property of equality subtraction property of equality?