It's the first one, an algebraic expression contains variables
I believe it's<span> 8cos(x)⁸ - 16cos(x)⁶ + 10cos(x)⁴ - 2cos(x)².
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Alternately, you can write [</span><span><span>1 / (tan(2x) - cot(2x))] + [cos(8x) / (tan(2x) - cot(2x))].
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Answer:
B
Step-by-step explanation:
Let x be the amount of Ann money, y be Jessica's money and z Mary money.
30% of z equates 0.3*z.
Ann has 30% less than z so: x = z - 0.3z = 0.7z.
70% of z equates 0.7z.
"Jessica has 70% more than Mary " we deduce the equation: y =z+0.7z= 1.7z.
Signe the total is $102, we deduce the equation x+y+z = 102.
x=0.7z and y=1.7z then 0.7z+1.7z+z=102, therefore 3.4z=102 then
z =102/3.4 = $30.
x=0.7*30= 21 and y=1.7*30=51.
Ann has $21, Mary has $30 and Jessica has $51.
The volume is 60 cubic inches.
To solve, follow the formula Volume = Length · Height · Width. If you are solving without a calculator, simply multiply the length and the height first, then multiply the product of that by the width, 2 / 3.
V = 10 · 9 · 2/3
V = (10 · 9) 2/3
V = 90 · 2/3
<span>V = 60 in.³
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Hope this helps. Good luck! :)