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1 year ago

Solve the quadractic equation 3x^2-5x-7=0

Mathematics

1 answer:

finlep [7]1 year ago

5 0

Answer:

2.113 and -0.446

Step-by-step explanation:

you have to use the formula x=-(b)+ or - the sqaure root of (b) squared-4 (a)(c) all over 2 (a).

You might be interested in

Which simplified fraction is equal to 0.53 with bar?

Oxana [17]

I assume that 0.53 with a bar means the decimal fraction in which 3 is repeating.

24/45, 8/15, and 48/90 all result in the same decimal value. Thus, we are simply looking for the one that is fully simplified.

The correct answer is 8/15.

Hope this helps!

5 0

1 year ago

Suppose we roll a fair die and let X represent the number on the die. (a) Find the moment generating function of X. (b) Use the

Likurg_2 [28]

Answer:

(a) moment generating function for X is $\frac{1}{6}\left(e^{t}+e^{2 t}+e^{2 t}+e^{4 t}+e^{5 t}+e^{6 t}\right)$

(b) $\mathrm{E}(\mathrm{X})=\frac{21}{6} \text { and } E\left(X^{2}\right)=\frac{91}{6}$

Step-by step explanation:

Given X represents the number on die.

The possible outcomes of X are 1, 2, 3, 4, 5, 6.

For a fair die, $P(X)=\frac{1}{6}$

(a) Moment generating function can be written as $M_{x}(t)$ .

$M_x(t)=\sum_{x=1}^{6} P(X=x)$

$M_{x}(t)=\frac{1}{6} e^{t}+\frac{1}{6} e^{2 t}+\frac{1}{6} e^{3 t}+\frac{1}{6} e^{4 t}+\frac{1}{6} e^{5 t}+\frac{1}{6} e^{6 t}$

$M_x(t)=\frac{1}{6}\left(e^{t}+e^{2 t}+e^{3 t}+e^{4 t}+e^{5 t}+e^{6 t}\right)$

(b) Now, find $E(X) \text { and } E\((X^{2})$ using moment generating function

$M^{\prime}(t)=\frac{1}{6}\left(e^{t}+2 e^{2 t}+3 e^{3 t}+4 e^{4 t}+5 e^{5 t}+6 e^{6 t}\right)$

$M^{\prime}(0)=E(X)=\frac{1}{6}(1+2+3+4+5+6)$

$\Rightarrow E(X)=\frac{21}{6}$

$M^{\prime \prime}(t)=\frac{1}{6}\left(e^{t}+4 e^{2 t}+9 e^{3 t}+16 e^{4 t}+25 e^{5 t}+36 e^{6 t}\right)$

$M^{\prime \prime}(0)=E(X)=\frac{1}{6}(1+4+9+16+25+36)$

$\Rightarrow E\left(X^{2}\right)=\frac{91}{6}$

Hence, (a) moment generating function for X is $\frac{1}{6}\left(e^{t}+e^{2 t}+e^{3 t}+e^{4 t}+e^{5 t}+e^{6 t}\right)$ .

(b) $\mathrm{E}(\mathrm{X})=\frac{21}{6} \text { and } E\left(X^{2}\right)=\frac{91}{6}$

6 0

3 years ago

800 g pineapple

neonofarm [45]

Answer:

30 people

Step-by-step explanation:

The question is as following:

Here are the ingredients for pineapple sherbet for 6 people

800g pineapple 4 egg whites 1/2 lemon 100g caster sugar

Dan makes pineapple sherbet he uses 2 1/2 lemons

work out how many people he makes pineapple sherbet for?

=======================================================

1/2 lemon needed for pineapple sherbet for 6 people

2 1/2 lemons needed for pineapple sherbet for x people

1/2 : 6 = 2 1/2 : x

∴ x = ( 6 * 2 1/2 ) ÷ (1/2)

x = 6 * 5/2 * 2 = 30 people

So, he make the pineapple sherbet for 30 people

5 0

3 years ago

Crank

Answer:

1/2

Step-by-step explanation:

6/12 = x/16

7 0

1 year ago

3 more than a number x

balu736 [363]

X+3 is the answer.zz

5 0

2 years ago

Read 2 more answers