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3 years ago

Which of the following is a solution to 2cos x + 1 = 0?

Mathematics

1 answer:

nlexa [21]3 years ago

3 0

The answer is b
2cos x + 1 = 0
2 cos x = -1
cos x = -1/2
x = cos^1(-1/2)
(cos inverse (-1/2))
x = 120°

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The height of a flare fired from a 32-foot

ahrayia [7]

Trace several round objects onto the grid on Math Masters, page 436

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3 years ago

The angle marked a = 75°.<br> Work out the value of x.<br><br> The diagram is not drawn accurately.

NikAS [45]

Answer:

x+75=180

x=180-75

x=105

Step-by-step explanation:

x and a are on a straight line

a straight line=180

so you add the x to a=180

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2 years ago

A magazine provided results from a poll of 1500 adults who were asked to identify their favorite pie. among the 1500 respondent

valentinak56 [21]

Answer:

0.01 is alpha level

Step-by-step explanation:

Given that a survey of a magazine of 1500 adults revealed that 12% chose chocolate pie.

i.e. p = proportion of people who like chocolate pie = 0.12

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The confidence level is given as 99%

Hence alpha = 1- confidence level

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Hence answer is 0.01

4 0

2 years ago

Read 2 more answers

Please help differentiate this!!!!!!!!!

vlada-n [284]

$\bf h=20ln(3t+2)+30\\\\
-------------------------------\\\\
\boxed{a}\\\\
\stackrel{0~years}{t=0}\qquad h=20ln[3(0)+2]+30\implies h=20ln(2)+30
\\\\\\
h\approx 43.86
\\\\\\
\boxed{b}\\\\
\stackrel{1~meter}{h=100}\qquad 100=20ln(3t+2)+30\implies 70=20ln(3t+2)
\\\\\\
\cfrac{70}{20}=ln(3t+2)\implies \stackrel{\textit{log cancellation rule}}{e^{\frac{7}{2}}=e^{ln(3t+2)}}\implies e^{\frac{7}{2}}=3t+2
\\\\\\
e^{\frac{7}{2}}-2=3t\implies \cfrac{e^{\frac{7}{2}}-2}{3}=t\implies 10.371817\approx t$

$\bf \boxed{c}\\\\
\cfrac{dh}{dt}=20\left(\cfrac{1}{3t+2}\cdot 3 \right)+0\implies \cfrac{dh}{dt}=20\left(\cfrac{3}{3t+2} \right)\\\\\\ \cfrac{dh}{dt}=\cfrac{60}{3t+2}
\\\\\\
\left. \cfrac{dh}{dt} \right|_{3}\implies \cfrac{60}{3(3)+2}\implies \cfrac{60}{11}
\\\\\\
\left. \cfrac{dh}{dt} \right|_{10}\implies \cfrac{60}{3(10)+2}\implies \cfrac{15}{8}$

5 0

3 years ago

Read 2 more answers

Two angles are supplementary. The measure of one angle is 54 more than the measure of the other angle. What is the measure of th

il63 [147K]

Answer:

bigger angle is 117°

Step-by-step explanation:

x+x+54= 180 (when two angles are complementary it means that their sum is 180 degrees)

2x+54=180

2x= 180-54

2x=128

x=126/2

x= 63

x1= smaller angle

x1= 63

x2= bigger angle

x2= 63+54

x2=117

4 0

3 years ago