### Home > A2C > Chapter 8 > Lesson 8.2.3 > Problem 8-147

8-147.

Ceirin's teacher promised a quiz for the next day, so Ceirin called Adel to review what they had done in class.

When they arrived at school the next morning, they compared the equations they had put in their graphing calculators while they talked on the phone. One had

*y*= sin2*x*− 1, while the other had*y*= sin2(*x*− 1).

Which equation was correct? Did they both subtract 1 from*x*? Explain. Describe the rule for shifting a graph one unit to the right in a way that avoids this confusion. Homework Help ✎

If you want to subtract 1 from *x* before multiplying, are parenthesis necessary?

The equation *y* = sin2(*x* − 1) is correct. To shift the graph one unit to the right, subtract 1 from *x* before multiplying by anything.