Math manuals in chez scheme

I could apply functions of sqrt and sin as

> (sqrt 35)
5.916079783099616
> (sin 1.57)
0.9999996829318346

in chez scheme's interactive shell,

but I cannot reference them in Chapter 8. Numeric Operations

Where are their manuals?

You can find the documentation for math functions in The Scheme Programming Language, Fourth Edition, Section 6.4. Numbers:

• sqrt
• sin