How can you prove polynomial identities and use them to describe numerical relationships? (100 point) ASAP

5,600 x 10^3 = a) 560 b) 5,000,600 c) 5,600,000 d) 56,000

Which of the expressions (on the photo document i inserted) together represent all solutions to the following equation? 8cos(12x)+4=-4 *the answer should be in degrees.* > i would like for someone to explain the process to find the solutions for this.

If t17 = 3 (t5) in an arithmetic progression, find t1 in terms of d.