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3 years ago

Help needed with these for problems

Mathematics

1 answer:

Tatiana [17]3 years ago

4 0

I can't read the first one and I also don't know

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How can I use fraction tiles to help me divide a whole number by a unit fraction

aniked [119]

sorry stranger but you can't use tiles if you want to go and count your tiles on the floor of your house

8 0

3 years ago

5cosx -2sin(x/2) +7=0<br>Help me to find x step by step<br>pls

miskamm [114]

Answer:

x = 180

Step-by-step explanation:

First, you need to know

1. Double-angle formula:

cos(2x) = $cos^{2}x - sin^{2}x$

2. Pythagorean identity:

$cos^{2}x + sin^{2}x = 1$

Back to your problem, replacing the variable by the above:

$5cosx-sin\frac{x}{2}+7 = 0$

$5(cos^{2}\frac{x}{2}-sin^{2}\frac{x}{2}) - 2sin\frac{x}{2} + 7 = 0$ By Double-angle formula

$5(1 - 2sin^{2}\frac{x}{2}) - 2sin\frac{x}{2} + 7 = 0$ By Pythagorean identity

Given $y = \frac{x}{2}$

$5(1-2sin^{2}y) - 2siny + 7 = 0$

$10sin^{2}y+2siny-12=0$

$5sin^{2}y+siny-6=0$

$(5siny + 6)(siny - 1)=0$ , we know -1 < sinx < 1, for every x ∈ R

$siny = 1, y =90$

$y = \frac{x}{2}$

$x = 180$

8 0

3 years ago

1. Is the square root of 2 between 1.3 and 1.4? How do you know?

VikaD [51]

Answer:

Step-by-step explanation:

1st . 1.3^2= 1.69

1.4^2= 1.96

It's not bettween 1.3 & 1.4

2. 1.4^2=1.96

1.5^2= 2.25

it's betteen 1.4 & 1.5

3 . 1.4 & 1.5 so it's eqaul 1.4

3 0

3 years ago

Read 2 more answers

It takes Bobby 12 hours longer to build a robot than it takes Alex. Together, they can build the Robot in 8 hours. How long does

anyanavicka [17]

Answer:

24 hours

Step-by-step explanation:

The computation of the number of hours taken by Bobby to build the robot by himself is shown below:

Given that

Bobby could take 12 hours

Together they could build in 8 hours

So based on the above information

the number of hours taken by Bobby to build the robot by himself is

Let us assume the above line be x

So,

$\frac{1}{8}-\frac{1}{12} = \frac{1}{x} \\\\\frac{6 - 4}{48} = \frac{1}{x} \\\\\frac{2}{48} = \frac{1}{x} \\\\x = \frac{48}{2}$

x = 24 hours

6 0

3 years ago

Help pliz Triangles ABC and DEF are similar.<br> Find the length of segment AC.

Natali5045456 [20]

Answer:

DE= 0.4

Step-by-step explanation:

8 0

3 years ago