Answer:
Step-by-step explanation:
The number of chapters read = y
Number of days spent to read = x
Slope of the line = ≈ 1.25
y-intercept = 2
Slope means "number of pages read per day"
For slope = 1.25 means "1.25 pages read per day"
y-intercept means "Number of pages read initially"
y-intercept = 2 means "2 pages have been already read"
This is not an identity but an equation. You're supposed to find the values of for which this is true. It is *not* true for all values of
.
To see why:
has period
, which means
.
The angle sum identity for says that
So
By definition of ,
and so
which is only 0 if either (which only happens for certain values of
) or
(which also only happens for certain values of
). It's these values of
you want to find.
whenever
is a multiple of
, i.e.
for any integer
.
If , then
is true for
and
. Then to account for all other possible values, we add a multiple of
, so that
or
for integers
.