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3 years ago

9

In a school, half of the 300 students saw Zootopia, 180 students saw Finding Dory, and 45 students did not see either movie. How

many students saw both movies?

2 answers:

tia_tia [17]3 years ago

7 0

Answer:

75 students watched both.

Step-by-step explanation:

150 students saw Zootopia

180 students saw Finding Dory

45 students saw nothing.

There are 300 students in total.

$|(300-45)-150-180|=\\|255-150-180|=\\|105-180|=\\|-75|=\\75$

kobusy [5.1K]3 years ago

4 0

Answer:

165 students (hope it helps)

Step-by-step explanation:

300students - 45students = 255students

180students + 150students = 330students

330students / 2 = 165

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interpret r(t) as the position of a moving object at time t. Find the curvature of the path and determine thetangential and norm

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Answer:

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The normal component of acceleration is $a_{\boldsymbol{N}}=1 (2)^2=4$

Step-by-step explanation:

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$\boldsymbol{r}'(t)=\frac{d}{dt}\left(cos\left(2t\right)\right)\:\boldsymbol{i}+\frac{d}{dt}\left(sin\left(2t\right)\right)\:\boldsymbol{j}+\frac{d}{dt}\left(1)\right\:\boldsymbol{k}\\\boldsymbol{r}'(t)=-2\sin \left(2t\right)\boldsymbol{i}+2\cos \left(2t\right)\boldsymbol{j}$

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The unit tangent vector is defined by

$\boldsymbol{T}}=\frac{\boldsymbol{r}'(t)}{||\boldsymbol{r}'(t)||}$

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$\frac{d}{dt}\left(2\right)\: = 0$ so

$a_{\boldsymbol{T}}=0$

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$a_{\boldsymbol{N}}=\kappa (\frac{ds}{dt})^2$

We know that $\kappa=1$ and $\frac{ds}{dt}=2$ so

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