Just simplify the following equation
2 (9.95) + 3 (11.99)
19.90 + 35.97
55.87 spent
Answer: 7/6
Step-by-step explanation:
If he is writing sixths, then we have multiples of 1/6.
this is:
0*(1/6) = 0
1*(1/6) = 1/6
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5*(1/6) = 5/6 (the numer he wrote at the left of 1)
6*(1/6) = 6/6 = 1
7*(1/6) = 7/6
So the number next to 1, (at the right of 1) must be 7/6.
You also can find it by adding 1/6 to 1.
1/6 + 1 = 1/6 + 6/6 = 7/6.
I don't think that anybody in Elementary School would Understand this you might want to post this question in the High School section.
Hope it gets answered :)
Answer:
f(x) = 8x⁴-8x²+1
Step-by-step explanation:
I will assume that f(cos θ) = cos(4θ). Otherwise, f would not be a polynomial. lets divide cos(4θ) in an expression depending on cos(θ). We use this properties
- cos(2a) = cos²(a) - sin²(b)
- sin(2a) = 2sin(a)cos(a)
- sin²(a) = 1-cos²(a)
cos(4θ) = cos(2 * (2θ) ) = cos²(2θ) - sin²(2θ) = [ cos²(θ)-sin²(θ) ]² - [2cos(θ)sin(θ)]² = [cos²(θ) - ( 1 - cos²(θ) ) ]² - 4cos²(θ)sin²(θ) = [2cos²(θ)-1]² - 4cos²(θ) (1 - cos²(θ) ) = 4 cos⁴(θ) - 4 cos²(θ) + 1 - 4 cos²(θ) + 4 cos⁴(θ) = 8cos⁴(θ) - 8 cos²(θ) + 1
Thus f(cos(θ)) = 8 cos⁴(θ) - 8 cos²(θ) + 1, and, as a result
f(x) = 8x⁴-8x²+1.
