$cox^4x-sin^4x=2cos^2x-1\\\\
(cosx^2-sin^2x)(cosx^2x+sin^2x)=2cos^2x-1\\\\
cosx^2-sin^2x*1=2cos^2x-1\ \ \ | subtract\ 2cos^2x\\\\
-cosx^2-sin^2x=-1\ \ \ | multiply\ by\ -1\\\\
cosx^2+sin^2x=1\\\\
1=1$

4 0

3 years ago

Jasmine works at the public library after school. She makes $7.00 per hour. She cannot work more than 15 hours per work. If y=7x

kotykmax [81]

Answer:

Step-by-step explanation:

Jasmine can work from 0 hours to 15 hours

6 0

3 years ago

Every year Mary invests $2000 in a savings account that earns interest at 10%

olya-2409 [2.1K]

Answer:

A = P(1 + r)t i think

Step-by-step explanation:

5 0

3 years ago

Find the solution of the system of equations. 7x -- 8y = -237x – 7y = -14(?,?)​

Find the solution of the system of equations. 7x -- 8y = -237x – 7y = -14(?,?)