Rationalise the denominator of 1/under root 7 + under root 6

Why do we need to know about unit rates

allochka39001 [22]

Answer:

because they allow us to make direct comparisons

Step-by-step explanation:

8 0

3 years ago

Find the volume of a cube that has the following dimensions:length=2x^2 width=x^3 height=x^2-6x+5 A) 4x^7-3x^6+8x^5 B) 2x^12-12x

fomenos

Answer:

Option D. 2x⁷ - 12x⁶ + 10x⁵

Step-by-step explanation:

From the question given:

Length (L) = 2x²

Width (w) = x³

Height (h) = x² - 6x + 5

Volume (V) =?

Volume (V) = length (L) x width (w) x height (h)

V = L x w x h

V = 2x² × x³ × x² - 6x + 5

V = (2x²) (x³) (x² - 6x + 5)

V = (2x⁵) (x² - 6x + 5)

Clear bracket

V = 2x⁷ - 12x⁶ + 10x⁵

Therefore, the volume of the cube is 2x⁷ - 12x⁶ + 10x⁵

4 0

3 years ago

Evaluate using <br> Definite integrals

swat32

Since $[0,4]=[0,1]\cup(1,4]$ , we can rewrite the integral as

$\displaystyle \int_0^1f(t)\;dt + \int_1^4 f(t)\; dt$

Now there is no ambiguity about the definition of f(t), because in each integral we are integrating a single part of its piecewise definition:

$\displaystyle \int_0^1f(t)\;dt = \int_0^11-3t^2\;dt,\quad \int_1^4 f(t)\; dt = \int_1^4 2t\; dt$

Both integrals are quite immediate: you only need to use the power rule

$\displaystyle \int x^n\;dx=\dfrac{x^{n+1}}{n+1}$

to get

$\displaystyle \int_0^11-3t^2\;dt = \left[t-t^3\right]_0^1,\quad \int_1^4 2t\; dt = \left[t^2\right]_1^4$

Now we only need to evaluate the antiderivatives:

$\left[t-t^3\right]_0^1 = 1-1^3=0,\quad \left[t^2\right]_1^4 = 4^2-1^2=15$

So, the final answer is 15.

4 0

3 years ago

A bag contains different colored candies. There are 50 candies in the bag, 28 are red, 10 are blue, 8 are green and 4 are yellow

Mrrafil [7]

Answer:

$\displaystyle \frac{54}{5405}$ .

Step-by-step explanation:

How many unique combinations are possible in total?

This question takes 5 objects randomly out of a bag of 50 objects. The order in which these objects come out doesn't matter. Therefore, the number of unique choices possible will the sames as the combination

$\displaystyle \left(50\atop 5\right) = 2,118,760$ .

How many out of that 2,118,760 combinations will satisfy the request?

Number of ways to choose 2 red candies out a batch of 28:

$\displaystyle \left( 28\atop 2\right) = 378$ .

Number of ways to choose 3 green candies out of a batch of 8:

$\displaystyle \left(8\atop 3\right)=56$ .

However, choosing two red candies out of a batch of 28 red candies does not influence the number of ways of choosing three green candies out of a batch of 8 green candies. The number of ways of choosing 2 red candies and 3 green candies will be the product of the two numbers of ways of choosing

$\displaystyle \left( 28\atop 2\right) \cdot \left(8\atop 3\right) = 378\times 56 = 21,168$ .