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3 years ago

9

Which one is the correct answer? And please show me the work you did

1 answer:

Andreas93 [3]3 years ago

4 0

18 monkeys will be right

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At Karl's Exact Ice-Cream, Karl fills each cone completely and tops it off with a scoop on top. Approximately how much ice-cream

hammer [34]

Answer:

Il existe de nombreux exemples de portfolios d’artistes en ligne. Trouvez-en un et partagez un lien vers celui-ci. En vous basant sur le portfolio, écrivez quelques phrases évaluant l'artiste. S'il y a les réponses d'autres élèves sur le forum de discussion, examinez-les et voyez si vous êtes d'accord ou pas d'accord avec leur opinion sur le travail des artistes.

8 0

3 years ago

Save me the headache

maxonik [38]

$(9\sin2x+9\cos2x)^2=81$

Taking the square root of both sides gives two possible cases,

$9\sin2x+9\cos2x=9\implies\sin2x+\cos2x=1$

or

$9\sin2x+9\cos2x=-9\implies\sin2x+\cos2x=-1$

Recall that

$\sin(\alpha\pm\beta)=\sin\alpha\cos\beta\pm\cos\alpha\sin\beta$

If $\alpha=2x$ and $\beta=\dfrac\pi4$ , we have

$\sin\left(2x+\dfrac\pi4\right)=\dfrac{\sin2x+\cos2x}{\sqrt2}$

so in the equations above, we can write

$\sin2x+\cos2x=\sqrt2\sin\left(2x+\dfrac\pi4\right)=\pm1$

Then in the first case,

$\sqrt2\sin\left(2x+\dfrac\pi4\right)=1\implies\sin\left(2x+\dfrac\pi4\right)=\dfrac1{\sqrt2}$

$\implies2x+\dfrac\pi4=\dfrac\pi4+2n\pi\text{ or }\dfrac{3\pi}4+2n\pi$

(where $n$ is any integer)

$\implies2x=2n\pi\text{ or }\dfrac\pi2+2n\pi$

$\implies x=n\pi\text{ or }\dfrac\pi4+n\pi$

and in the second,

$\sqrt2\sin\left(2x+\dfrac\pi4\right)=-1\implies\sin\left(2x+\dfrac\pi4\right)=-\dfrac1{\sqrt2}$

$\implies2x+\dfrac\pi4=-\dfrac\pi4+2n\pi\text{ or }-\dfrac{3\pi}4+2n\pi$

$\implies2x=-\dfrac\pi2+2n\pi\text{ or }-\pi+2n\pi$

$\implies x=-\dfrac\pi4+n\pi\text{ or }-\dfrac\pi2+n\pi$

Then the solutions that fall in the interval $[0,2\pi)$ are

$x=0,\dfrac\pi4,\dfrac\pi2,\dfrac{3\pi}4,\pi,\dfrac{5\pi}4,\dfrac{3\pi}2,\dfrac{7\pi}4$

5 0

3 years ago

Read 2 more answers

What is an algebraic expression for 'two thirds of a number (d) to the third power' ?

horrorfan [7]

It is (2/3d)^3
Make sure the exponent is on the outside. This is because you are raising 2/3d. Not just D

5 0

2 years ago

Read 2 more answers

In △CDE , CD=12 , DE=5 , and m∠E=83∘ .<br><br> What is m∠D to the nearest tenth of a degree?

mr_godi [17]

Answer:

As law of sin:

CD/sinE = DE/sinC

Then

12/sin83 = 5/sinC

Then

sinC = 5*sin83/12 = 0.413

Then

C = arcsin(0.413) = ~24.4 deg

Then

D = 180-C-E = 180-83-24.4 = ~72.6

Hope this help, bro!

3 0

2 years ago

Write the standard equation for the circle

saw5 [17]

Answer:

The standard form of a circle's equation is (x-h)² + (y-k)² = r² where (h,k) is the center and r is the radius.

Step-by-step explanation:

3 0

2 years ago