Factor completely 3x^2 − x − 4.

Find the value of the following expression (2^8 • 3^-5 • 6^0) write your answer in simplified form show all your steps Help Fast

vitfil [10]

${( {2}^{8} \times {3}^{ - 5} \times {6}^{0} })^{ - 2} \\ = \frac{1}{ {( {2}^{8} \times {3}^{ - 5} \times {6}^{0} })^{2} } \\ = \frac{1}{ {(256 \times \frac{1}{ {3}^{5} } \times 1 })^{2} } \\ = \frac{1}{ {(256 \times \frac{1}{243} \times 1 })^{2} } \\ = \frac{1}{ ({ \frac{256}{243} })^{2} } \\ = \frac{1}{ \frac{ {256}^{2} }{ {243}^{2} } } \\ = \frac{1}{ \frac{65536}{59049} } \\ = \frac{59049}{65536}$
The answer is 59049/65539
The value is 0.901

6 0

3 years ago

A line tangent to the curve f(x)=1/(2^2x) at the point (a, f(a)) has a slope of -1. What is the x-intercept of this tangent?

kirza4 [7]

Answer:

x-intercept = 0.956

Step-by-step explanation:

You have the function f(x) given by:

$f(x)=\frac{1}{2^{2x}}$ (1)

Furthermore you have that at the point (a,f(a)) the tangent line to that point has a slope of -1.

You first derivative the function f(x):

$\frac{df}{dx}=\frac{d}{dx}[\frac{1}{2^{2x}}]$ (2)

To solve this derivative you use the following derivative formula:

$\frac{d}{dx}b^u=b^ulnb\frac{du}{dx}$

For the derivative in (2) you have that b=2 and u=2x. You use the last expression in (2) and you obtain:

$\frac{d}{dx}[2^{-2x}]=2^{-2x}(ln2)(-2)$

You equal the last result to the value of the slope of the tangent line, because the derivative of a function is also its slope.

$-2(ln2)2^{-2x}=-1$

Next, from the last equation you can calculate the value of "a", by doing x=a. Furhtermore, by applying properties of logarithms you obtain:

$-2(ln2)2^{-2a}=-1 \\\\2^{2a}=2(ln2)=1.386\\\\log_22^{2a}=log_2(1.386)\\\\2a=\frac{log(1.386)}{log(2)}\\\\a=0.235$

With this value you calculate f(a):

$f(a)=\frac{1}{2^{2(0.235)}}=0.721$

Next, you use the general equation of line:

$y-y_o=m(x-x_o)$

for xo = a = 0.235 and yo = f(a) = 0.721:

$y-0.721=(-1)(x-0.235)\\\\y=-x+0.956$

The last is the equation of the tangent line at the point (a,f(a)).

Finally, to find the x-intercept you equal the function y to zero and calculate x:

$0=-x+0.956\\\\x=0.956$

hence, the x-intercept of the tangent line is 0.956

5 0

2 years ago

What is 20,700,0000 in standard notation?

alexdok [17]

Answer:

2.07 x 10^4

Step-by-step explanation:

8 0

3 years ago

Part 1: Use the information provided to write the standard form equation of each circle. Please show the work.

dusya [7]

Answer:

1. (x + 2)² + (y - 9)² = 64

2. (x + 6)² + (y - 9/2)² = 100

3. (x - 15)² + (y + 10)² = 1

Step-by-step explanation:

Equation of a circle:

(x - h)² + (y - k)² = r²

1. Center: (-2, 9), Radius: 8

(x - (-2))² + (y - 9)² = 8²

(x + 2)² + (y - 9)² = 64

2. Center: (-6, 9/2), Radius: 10

(x - (-6))² + (y - (9/2))² = 10²

(x + 6)² + (y - 9/2)² = 100

3. Center: (15, -10), Radius: 1

(x - 15)² + (y - (-10))² = 1²

(x - 15)² + (y + 10)² = 1

4 0

3 years ago

It takes 1 1/3 hours to set up 1/3 of an hour to run and 2/3 of an hour to verify the results. How many hours will it take to co

liraira [26]

Answer: It will take $\frac{7}{3}$ of an hour to complete the test.

Step-by-step explanation:

We need to convert the mixed number $1\ \frac{1}{3}$ to an improper fraction:

$1\ \frac{1}{3}=\frac{(1*3)+1}{3}= \frac{4}{3}$

Now, we need to make the following add the fractions in order to calculate how many hours will it take to complete the test. Then, we get:

$\frac{4}{3}+\frac{1}{3}+\frac{2}{3}=\frac{4+1+2}{3}=\frac{7}{3}$

Therefore, it will take $\frac{7}{3}$ of an hour to complete the test.

5 0

3 years ago