Estimate the square root or round to the nearest integer √17,√242,√320

Click an item in the list or group of pictures at the bottom of the problem and, holding the button down, drag it into the corre

FromTheMoon [43]

$\\ \sf\longmapsto \dfrac{7x}{15}-1=22$

$\\ \sf\longmapsto 7x/15=23$

$\\ \sf\longmapsto 7x=345$

$\\ \sf\longmapsto x=345/7$

$\\ \sf\longmapsto x\approx 49$

8 0

2 years ago

Which number produces an irrational number when added to 0.4

elena-14-01-66 [18.8K]

Any other irrational number. 0.4 is rational (ie., it can be written as a fraction), but rational+irrational is always irrational.

So examples would be π or √2. If you add those, the result is irrational.

6 0

4 years ago

!PLEASE HELP ME!

Mkey [24]

Answer:

We conclude that Tim is correct when he says that the expression x² only yields values that are positive.

Step-by-step explanation:

Given the expression

x²

Plug in and checking x = 1 and x = -1 in the expression

Putting x = 1 in the expression

x²= (1)² = 1

Putting x = -1 in the expression

x²= (-1)² = 1

Thus, the expression yields the same output '1' when we enter x = 1, and x=-1.

Plug in and checking x = 2 and x = -2 in the expression

Putting x = 2 in the expression

x²= (2)² = 4

Putting x = -1 in the expression

x²= (-2)² = 4

Thus, the expression yields the same output '4' when we enter x = 2, and x=-2.

Plug in and checking x = 3 and x = -3 in the expression

Putting x = 3 in the expression

x²= (3)² = 9

Putting x = -1 in the expression

x²= (-3)² = 9

Thus, the expression yields the same output '9' when we enter x = 3, and x=-3.

The reason why the expression x² only yields positive values because the expression is in the square form, and the square of any number will always yield a positive value, no matter whether the input number is negative or positive.

Therefore, we conclude that Tim is correct when he says that the expression x² only yields values that are positive.

3 0

3 years ago

PLSSS HELP 50 POINTSSS Select the correct answer.

Margarita [4]

I think the answer is D but I could be wrong

3 0

3 years ago

HELP ASAP FOR BRAINLIEST!

salantis [7]

Answer:

make sure calculator is in "radians" mode
use the cos⁻¹ function to find cos⁻¹(.23) ≈ 1.338718644

Step-by-step explanation:

A screenshot of a calculator shows the cos⁻¹ function (also called arccosine). It is often a "2nd" function on the cosine key. To get the answer in radians, the calculator must be in radians mode. Different calculators have different methods of setting that mode. For some, it is the default, as in the calculator accessed from a Google search box (2nd attachment).

__

The third attachment shows a graph of the cosine function (red) and the value 0.23 (dashed red horizontal line). Everywhere that line intersects the cosine function is a value of A such that cos A = 0.23. There are an infinite number of them. You need to know about the symmetry and periodicity of the cosine function to find them all, given that one of them is A ≈ 1.339.

The solution in the 4th quadrant is at 2π-1.339, and additional solutions are at these values plus 2kπ, for any integer k.

__

Also in the third attachment is a graph of the inverse of the cosine function (purple). The dashed purple vertical line is at x=0.23, so its intersection point with the inverse function is at 1.339, the angle at which cos(x)=0.23. The dashed orange graph shows the inverse of the cosine function, but to make it be single-valued (thus, a function), the arccosine function is restricted to the range 0 ≤ y ≤ π (purple).

_____

So, the easiest way to answer the problem is to use the inverse cosine function (cos⁻¹) of your scientific or graphing calculator. (Always make sure the angle mode, degrees or radians, is appropriate to the solution you want.) Be aware that the cosine function is periodic, so there is not just one answer unless the range is restricted.

__

I keep myself "unconfused" by reading cos⁻¹ as the angle whose cosine is. As with any inverse functions, the relationship with the original function is ...

cos⁻¹(cos A) = A

cos(cos⁻¹ a) = a

5 0

4 years ago