I need help with these problems please and thank you

Mathematics

2 answers:

AURORKA [14]3 years ago

7 0

Answer:

Refractive index of a medium depends upon the refractive index of the surroundings

artcher [175]3 years ago

4 0

Answer:

5. There are 4 coins in every punch

6. There are 5 coins in every punch

7. There is 1 coin in every punch

8. There aren't coins in the punches

Step-by-step explanation:

$4x+2=18\\4x=18-2\\4x=16\\x=\frac{16}{4} \\x=4$

$3x+5=20\\3x=20-5\\3x=15\\x=\frac{15}{3}\\x=5$

$2x+10=9+3x\\x+-3x=9-10\\-1x=-1\\x=1$

$2x+14=14\\2x=14-14\\2x=0\\x=\frac{0}{2}\\x=0$

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Which pair of angles are an example of alternate exterior angles?

9966 [12]

Answer:

c. is the answer becuase since it is exterior they are talking about the outside of the parellel lines.

Step-by-step explanation:

4 0

3 years ago

Read 2 more answers

Leno4ka [110]

Answer:

$\frac{s^2-25}{(s^2+25)^2}$

Step-by-step explanation:

Let's use the definition of the Laplace transform and the identity given: $\mathcal{L}[t \cos 5t]=(-1)F'(s)$ with $F(s)=\mathcal{L}[\cos 5t]$ .

Now, $F(s)=\int_0 ^{+ \infty}e^{-st}\cos(5t) dt$ . Using integration by parts with u=e^(-st) and dv=cos(5t), we obtain that $F(s)=\frac{1}{5}\sin(5t)e^{-st} |_{0}^{+\infty}+\frac{s}{5}\int_0 ^{+ \infty}e^{-st}\sin(5t) dt=\int_0 ^{+ \infty}e^{-st}\sin(5t) dt$ .

Using integration by parts again with u=e^(-st) and dv=sin(5t), we obtain that

$F(s)=\frac{s}{5}(\frac{-1}{5}\cos(5t)e^{-st} |_{0}^{+\infty}-\frac{s}{5}\int_0 ^{+ \infty}e^{-st}\sin(5t) dt)=\frac{s}{5}(\frac{1}{5}-\frac{s}{5}\int_0^{+ \infty}e^{-st}\sin(5t) dt)=\frac{s}{5}-\frac{s^2}{25}F(s)$ .