### Home > INT3 > Chapter 9 > Lesson 9.2.2 > Problem9-109

9-109.
1. Susan knows how to shift y = sin(x) to get the graph at right, but she wonders if it is possible to get the same graph by shifting y = cos(x). Homework Help ✎

1. Is it possible to write a cosine function for this graph?

2. If you think writing a cosine function is possible, write an equation that has cosine. If you think writing one is impossible, explain why.

3. Adlai says, “I can get that graph without shifting to the right or left.” What equation does he write?

Yes, it is.

The graph of y = cos (x) starts at a maximum. This graph has a maximum at

$x = - \frac{\pi}{2} .$

y = −sin(x)