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2 years ago

Multiply (3x-5)(x+4)

Mathematics

2 answers:

Allisa [31]2 years ago

4 0

Answer:

3x^2+7x-20

Step-by-step explanation:

77julia77 [94]2 years ago

3 0

Answer:

expand the brackets

3x^2 + 7x -20

Step-by-step explanation:

(3x-5)(x+4)

= 3x^2 + 12x - 5x + 20

= 3x^2 + 7x + 20

You might be interested in

Calculate the limit values:

Nataliya [291]

A) This particular limit is of the indeterminate form,
$\frac{ \infty }{ \infty }$
if we plug in infinity directly, though it is not a number just to check.

If a limit is in this form, we apply L'Hopital's Rule.

's
$Lim_{x \rightarrow \infty } \frac{ ln(x ^{2} + 1 ) }{x} = Lim_ {x \rightarrow \infty } \frac{( ln(x ^{2} + 1 ) ) '}{x ' }$
So we take the derivatives and obtain,

$Lim_ {x \rightarrow \infty } \frac{ ln(x ^{2} + 1 ) }{x} = Lim_{x \rightarrow \infty } \frac{ \frac{2x}{x^{2} + 1} }{1}$

Still it is of the same indeterminate form, so we apply the rule again,

$Lim_{x \rightarrow \infty } \frac{ ln(x ^{2} + 1 ) }{x} = Lim_{x \rightarrow \infty } \frac{ 2 }{2x}$

This simplifies to,

$Lim_{x \rightarrow \infty } \frac{ ln(x ^{2} + 1 ) }{x} = Lim_{x \rightarrow \infty } \frac{ 1 }{x} = 0$

b) This limit is also of the indeterminate form,

$\frac{0}{0}$
we still apply the L'Hopital's Rule,

$Lim_ {x \rightarrow0 }\frac{ tanx}{x} = Lim_ {x \rightarrow0 } \frac{ (tanx)'}{x ' }$

$Lim_ {x \rightarrow0 }\frac{ tanx}{x} = Lim_ {x \rightarrow0 } \frac{ \sec ^{2} (x) }{1 }$

When we plug in zero now we obtain,

$Lim_ {x \rightarrow0 }\frac{ tanx}{x} = Lim_ {x \rightarrow0 } \frac{ \sec ^{2} (0) }{1 } = \frac{1}{1} = 1$
c) This also in the same indeterminate form

$Lim_ {x \rightarrow0 }\frac{ {e}^{2x} - 1 - 2x}{ {x}^{2} } = Lim_ {x \rightarrow0 } \frac{ ({e}^{2x} - 1 - 2x)'}{( {x}^{2} ) ' }$

$Lim_ {x \rightarrow0 }\frac{ {e}^{2x} - 1 - 2x}{ {x}^{2} } = Lim_ {x \rightarrow0 } \frac{ (2{e}^{2x} - 2)}{ 2x }$

It is still of that indeterminate form so we apply the rule again, to obtain;

$Lim_ {x \rightarrow0 }\frac{ {e}^{2x} - 1 - 2x}{ {x}^{2} } = Lim_ {x \rightarrow0 } \frac{ (4{e}^{2x} )}{ 2 }$

Now we have remove the discontinuity, we can evaluate the limit now, plugging in zero to obtain;

$Lim_ {x \rightarrow0 }\frac{ {e}^{2x} - 1 - 2x}{ {x}^{2} } = \frac{ (4{e}^{2(0)} )}{ 2 }$

This gives us;

$Lim_ {x \rightarrow0 }\frac{ {e}^{2x} - 1 - 2x}{ {x}^{2} } =\frac{ (4(1) )}{ 2 }=2$

d) $Lim_ {x \rightarrow +\infty }\sqrt{x^2+2x}-x$

For this kind of question we need to rationalize the radical function, to obtain;

$Lim_ {x \rightarrow +\infty }\frac{2x}{\sqrt{x^2+2x}+x}$

We now divide both the numerator and denominator by x, to obtain,

$Lim_ {x \rightarrow +\infty }\frac{2}{\sqrt{1+\frac{2}{x}}+1}$

This simplifies to,

$=\frac{2}{\sqrt{1+0}+1}=1$

5 0

3 years ago

Which represents the polynomial written in standard form? 8x2y2 – StartFraction 3 x cubed y Over 2 EndFraction 4x4 – 7xy3 –7xy3

olga55 [171]

Polynomial equation is a equation which is formed with coefficients variables and exponents with basic mathematics operation and equality sign. The given option the option A matches correctly with the above polynomial equation which is,

$-7xy^3+8x^2y^2-\dfrac{3x^3y}{2}+4x^4$

Hence the option A is the correct option.

<h3>Given information-</h3>

The given polynomial equation in the problem is,

$8x^2y^2-\dfrac{3x^3y}{2}+4x^4-7xy^3$

<h3>Polynomial equation </h3>

Polynomial equation is a equation which is formed with coefficients variables and exponents with basic mathematics operation and equality sign.

In the above polynomial equation the variable are<em> x </em>and <em>y </em>and the highest power of the variable <em>x</em> is four and highest power of the variable <em>y</em> is three.

Arrange the polynomial equation in the power of the variable <em>x. </em>Thus,

$4x^4-\dfrac{3x^3y}{2}+8x^2y^2-7xy^3$

Arrange the polynomial equation in the power of the variable <em>y. </em>Thus,

$-7xy^3+8x^2y^2-\dfrac{3x^3y}{2}+4x^4$

From the given option the option A matches correctly with the above polynomial equation which is,

$-7xy^3+8x^2y^2-\dfrac{3x^3y}{2}+4x^4$

Thus the option A is the correct option.

Learn more about the polynomial equation here;

brainly.com/question/25958000

8 0

2 years ago

Find the central angle of a sector of a circle of the area of the sector and the area of the circle are in the proportion of 3:5

abruzzese [7]

Answer:

$\theta = 216$

Step-by-step explanation:

Given

Area of Sector : Area of Circle = 3 : 5

Required

Determine the central angle

The question implies that

$\frac{Area_{sector}}{Area_{circle}} = \frac{3}{5}$

Multiply both sides by 5

$5 * \frac{Area_{sector}}{Area_{circle}} = \frac{3}{5} * 5$

$5 * \frac{Area_{sector}}{Area_{circle}} = 3$

Multiply both sides by Area{circle}

$5 * \frac{Area_{sector}}{Area_{circle}} * Area_{circle} = 3 * Area_{circle}$

$5 * {Area_{sector} = 3 * Area_{circle}$

Substitute the areas of sector and circle with their respective formulas;

$Area_{sector} =\frac{\theta}{360} * \pi r^2$

$Area_{circle} = \pi r^2$

So, we have

$5 * \frac{\theta}{360} * \pi r^2 = 3 * \pi r^2$

Divide both sides by $\pi r^2$

$5 * \frac{\theta}{360} * \frac{ \pi r^2}{\pi r^2} = 3 * \frac{\pi r^2}{\pi r^2}$

$5 * \frac{\theta}{360} = 3$

Multiply both sides by 360

$360 * 5 * \frac{\theta}{360} = 3 * 360$

$5 * \theta = 3 * 360$

Divide both sides by 5

$\frac{5 * \theta}{5} = \frac{3 * 360}{5}$

$\theta = \frac{3 * 360}{5}$

$\theta = \frac{1080}{5}$

$\theta = 216$

Hence, the central angle is 216 degrees

3 0

2 years ago

Deborah needs to make 16 costumes for the school play. Each costume requires 2 and 1/4 yards of material. How many yards of mate

patriot [66]

35.5 wouldn’t be enough. She needs 2 1/4 of yards of material, first you would need to convert the fraction into a decimal and 1/4 is .25 which gives you 2.25 now you multiply 16 x 2.25 which gives you 36. That’s why 35.5 wouldn’t be enough.

3 0

3 years ago

The height of a right cylinder is 3r , where r is the radius. Write a function f in simplest form that represents the ratio of t

son4ous [18]

Answer:

I think it's 9 again I think

Step-by-step explanation:

7 0

2 years ago