# Evaluate the expression of 1/2 x3 when x = 4

Step-by-step explanation:

1/2 x3 = x4/2

x=4

3 x 4 = 12

12/2 = 6

## Related Questions

Every day, you take the elevator from the basement parking lot that is at level-3. The elevator takes twoseconds per level and you find that it takes 46 seconds to reach your floor.
Which floor do you live on?

23 is the floor which you live on

WILL MARK BRAINLIEST ONLY HAVE 30 MINUTES

Step-by-step explanation:

its 21

Step-by-step explanation:

you add 9 +12= 21 inches

Enter the range of values for x

Greetings from Brasil...

See the attached figure. The smaller the θ angle, the smaller the AB side will be. If the angle θ = 90º, then AB = 25. As θ < 90, then AB < 25

5X - 10 < 25

5X < 25 + 10

X < 35/5

X < 7

The AB side can be neither zero nor negative. So

5X - 10 > 0

5X > 10

X > 10/5

X > 2

### 2 < X < 7

Part A How much voltage must be used to accelerate a proton (radius 1.2 ×10−15m) so that it has sufficient energy to just penetrate a silicon nucleus? A silicon nucleus has a charge of +14e, and its radius is about 3.6 ×10−15m. Assume the potential is that for point charges.

Step-by-step explanation:

Qp = charge on proton = 1.6 x 10-19 C

Qs = charge on silicon = 14 x 1.6 x 10-19 C

rf = final distance from nucleus = ∞

ri = initial distance from nucleus = (3.6 x 10-15 + 1.2 x 10-15 ) = 4.8 x 10-15 m

initial Potential energy is given as

Ui = k Qp Qs / ri = (9 x 109) (1.6 x 10-19 ) (14 x 1.6 x 10-19 ) / (4.8 x 10-15 ) = 6.72 x 10-13 J

final Potential energy is given as

Uf = k Qp Qs / rf = (9 x 109) (1.6 x 10-19 ) (14 x 1.6 x 10-19 ) / (∞) = 0 J

Change in Potential energy = ΔU = Ui - Uf = 6.72 x 10-13 - 0 = 6.72 x 10-13 J

Let the Voltage through which proton is accelerated = V

Energy gained due to potential difference = Qp V

Using conservation of energy

Qp V = 6.72 x 10-13

(1.6 x 10-19 ) V = 6.72 x 10-13

V = 4.2 x 106 volts

How to solve this type of question

In general, you solve questions of cancavity by looking at the second derivative. It will be negative where the function is concave downward. (It will be positive for concave upward, and zero at points of inflection.)

I find it convenient to get guidance from a graphing calculator.

f(x) is concave downard on the interval (-∞, 2).

_____
The derivative is
.. f'(x) = e^-x -x*e^-x
The second derivative is
.. f''(x) = -e^-x -(e^-x -x*e^-x)
.. = (x -2)*e^-x
This will be negative for x < 2.

WILL GIVE BRAINLIEST IF CORRECT!!How many different 7-digit positive integers exist? (Note that we don't allow "7-digit" integers that start with 0, such as 0123456; this is actually a 6-digit integer.)

There are 9,000,000 seven-digit positive integers.

Explanation:

For the first digit, we have 9 choices: 1, 2, 3, 4, 5, 6, 7, 8, 9.

For each remaining digit, we have 10 choices: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9.

Each choice is independent of the others. So, the number of total 7-digit positive integers is the product of all the numbers of choices for each digit.

hope it helps

need brainliest......

Since 0 cannot be put as the first digit, there are 9 choices for the first digit, and the next 6 digits have 10 choices. So, there are 9 × 10^6 = 9000,000 numbers.