The answer is B x is greater than -5 and less than 3
Answer:
f(-4) = 5
Step-by-step explanation:
Explanation of
_
| 5, x < -3
f(x) | 2x² - 4, -3 ≤ x ≤ 4
| 1 - 6x , x > 4
_
When the x in f(x) is less than -3 than f(x) = 5
When the x in f(x) is greater than -3 but less than 4 then f(x) = 2x² - 4
When the x in f(x) is greater than 4 than f(x) = 1 - 6x
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Now that we know this lets look back at the question.
We want to find f(-4).
Looking at the piece wise function we see that f(-4) follow x < -3 as "x" or -4 is less than -3. When x is less than -3, f(x) = 5, hence f(-4) = 5
Answer:
√
8
≈
3
Explanation:
Note that:
2
2
=
4
<
8
<
9
=
3
2
Hence the (positive) square root of
8
is somewhere between
2
and
3
. Since
8
is much closer to
9
=
3
2
than
4
=
2
2
, we can deduce that the closest integer to the square root is
3
.
We can use this proximity of the square root of
8
to
3
to derive an efficient method for finding approximations.
Consider a quadratic with zeros
3
+
√
8
and
3
−
√
8
:
(
x
−
3
−
√
8
)
(
x
−
3
+
√
8
)
=
(
x
−
3
)
2
−
8
=
x
2
−
6
x
+
1
From this quadratic, we can define a sequence of integers recursively as follows:
⎧
⎪
⎨
⎪
⎩
a
0
=
0
a
1
=
1
a
n
+
2
=
6
a
n
+
1
−
a
n
The first few terms are:
0
,
1
,
6
,
35
,
204
,
1189
,
6930
,
...
The ratio between successive terms will tend very quickly towards
3
+
√
8
.
So:
√
8
≈
6930
1189
−
3
=
3363
1189
≈
2.828427
You write it as 46 divide by 1058. 46 x 2 is the closest you will get to 100. 46 x 2 is 92. put it in and you have 138 left. multiply 46 x 3 and you will get 138. amswer is 23. remember to bring down the next number whwn dividing
