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3 years ago

Find all solutions to the equation. cos2x + 2 cos x + 1 = 0

1 answer:

5 0

For cos(2x) * (2cos(x) + 1) = 0, use the double angle identity for cos(2x), which is cos^2 x - sin^2 x = cos^2 x - (1-cos^2) = 2cos^2 x - 1.
So we have (2cos^2 x - 1)(2cos x + 1) = 0. So 2cos^2 x -1 = 0 or x = 0 and 2pi.
For 2sec^2 x + tan^2 x - 3 = 0, use the identity sec^2 x = tan^2 x + 1, so we have
2(tan^2 x + 1) + tan^2 x - 3 = 0 or
2tan^2 x + tan^2 x - 1 = 0 or
3 tan^2 x = 1.

So x = pi/2, pi/2 + pi = 3pi/2.

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What is the value of S5? S5 = RETRY

Sphinxa [80]

Answer:

The answer is 50

Step-by-step explanation:

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3 years ago

Joan Messineo borrowed $47,000 at a 5% annual rate of interest to be repaid over 3 years. The loan is amortized into three eq

tester [92]

Answer:

a) The value of the Annual Payment is A=$17,258.80

b) Is the picture in the attachment file

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Step-by-step explanation:

a) First of all, we are going to list the Knowns: $VP=47000$ , $i=5$ % and $n=3$ , Then we can use $A=\frac{VP}{\frac{1-(1+i)^{-n} }{i} } =\frac{47000}{\frac{1-(1+0.05)^{-3} }{0.03} }=17258.80$ . So this is the value of the Annual Payment

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3 years ago

Find the x intercepts of f(x) = –16x^2 + 22x + 3

Helga [31]

That is where the line crosses the x axis or where y=0

0=-16x^2+22x+3
we gon do grouping
ac method
-16 times 3=-48

what 2 numbers multiply to get -48 and add to get 22
-2 and 24
0=-16x^2-2x+24x+3
group
0=(-16x^2-2x)+(24x+3)
undistribute
0=-2x(8x+1)+3(8x+1)
undistribute
0=(8x+1)(-2x+3)
set eaqual to 0

8x+1=0
8x=-1
x=-1/8

-2x+3=0
3=2x
3/2=x

x intercepts ate x=-1/8 and x=3/2

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3 years ago

-2/5 + 1 1/13 Find the sum

Goshia [24]

Answer:0.67692307692

Step-by-step explanation: d

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3 years ago

Assume that the profit generated by a product is given by where x is the number of units sold. If the profit keeps changing at a

scoray [572]

Answer:

21794.495 units/month

Step-by-step explanation:

Some data are missing which i can assume as per requirement of the Question.

Let us consider that profit generated by a product is given by

p(x) =4√x

Also, consider that the profit keeps changing at a rate of $1000 per month.

Now, Using the chain rule we can write

dp/dx=(dp/dt)÷(dx/dt).

So, we can calculate

dp/dx=2x^(-1/2)=2/√x.

As per question we have to find out dx/dt

Since, dx/dt= (dp/dt)/(dp/dx),

so plugging x=1900 we get 1000√1900/2=21794.495 units/month increase in sales.

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3 years ago