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Aliun [14]
3 years ago
5

Sin78 ×cos42+cos78×sin42 evaluate without the use of a calculator

Mathematics
1 answer:
Novay_Z [31]3 years ago
4 0
Sin a * cos b + cos a * sin b=sin (a+b)

sin 78 * cos 42 + cos 78* sin 42=sin (78+42)=sin 120=sin(180-120)=
sin 60=√3 / 2

Answer: sin 78 * cos 42 + cos 78* sin 42=<span>√3 / 2</span>
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Step-by-step explanation:

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3 years ago
while digging in the background, you find an old coin. its mass is 26.76 g qnd its volume is 3cm3. what is the coin made of?
tresset_1 [31]

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Step-by-step explanation:

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Write the point-slope form of the equation of the line that passes through the points (-3, 5) and (-1, 4). Please answer quickly
Oksanka [162]
The point-slope form of the equation of a line is

y - y_1 = m(x - x_1)

where

(x_1, y_1)

is a point on the line, and

m

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We can use either one of the two given points as the point on the line.
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The slope of the line that passes through points

(x_1, y_1) and (x_2, y_2)

is

m = \dfrac{y_2 - y_1}{x_2 - x_1}

Let's find the slope using (-3, 5) as point 1 and (-1, 4) as point 2.

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Now we use the point-slope formula with point 1 and the slope we found just above.

y - y_1 = m(x - x_1)

y - 5 = -\dfrac{1}{2}(x - (-3))
4 0
3 years ago
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Evaluate 5 + (-4) +(-7) + 2.
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Answer:

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Step-by-step explanation:

4 0
3 years ago
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