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3 years ago

F(x)= 3x^2+5x-8. Solve the quadratic equation

Mathematics

1 answer:

7nadin3 [17]3 years ago

7 0

Answer:

$\bold{x_1=1\ ,\quad x_2=-\dfrac83}$

Step-by-step explanation:

$3x^2+5x-8=0\quad\implies\quad a=3\,,\ b=5\,,\ c=-8\\\\x=\dfrac{-5\pm\sqrt{5^2-4(3)(-8)}}{2\cdot3}=\dfrac{-5\pm\sqrt{25+96}}{6}=\dfrac{-5\pm\sqrt{121}}{6}\\\\ x_1=\dfrac{-5+11}{6}=1\ ,\qquad x_2=\dfrac{-5-11}{6}=\dfrac{-16}6=-\dfrac83$

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Pleasee help mee<br><br>12sin(x)-5cos(x)=6,5

abruzzese [7]

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r = 13 Ф=arctan(-12/5) + 180° ( in the second quadrant )

so -5 = 13 cos Ф, 12 = 13 sin Ф

12 sin x - 5 cos x = 6.5

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13 cos(x - Ф) = 6.5

cos(x - Ф) = 1/2

cos(x - Ф) = cos 60°

x - Ф = ± 60° + 360° k integer k

x = Ф ± 60° + 360° k

x = 180° + arctan(-12/5) ± 60° + 360° k

That's the exact answer;

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3 years ago

An employee was randomly chosen from a company. If the expected value of the age of the employee is _____ years old, the mean ag

Vinil7 [7]

This employee who was randomly chosen represents the population of the company. This means that, any parameter measured through this employee can be considered as the mean or average value for the whole population (the company).

Based on this, taking the age of the employee as the desired parameter, the age of this employee will be considered as the average or mean age for the whole company. This means that the age of the employee and the mean age of all employees are equal.

Therefore, the answer is C) 32, 32
<span>An employee was randomly chosen from a company. If the expected value of the age of the employee is 32 years old, the mean age of all the employees in the company is 32 years old.</span>

5 0

3 years ago

Read 2 more answers

There is 1/3 of a carrot in every container of salad.

snow_tiger [21]

Answer:

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Step-by-step explanation:

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2 years ago

Nikita invests $2,000 into a bank account with a 4% annual interest rate. In seven years, which is the most expensive item she c

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Answer:

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Provided that Nikita is spending money that she had invested and the amount she collected over the period of 7 years. She can buy any item that costs no more than $2,560.00 but how?

It is a problem of simple interest:

Here the principal amount (P) = $2,000.00

Interest rate (r) = 4%

Time period (t) = 7 years

So, total amount that she would get by the end of 7 years is:

$A=P+SI$