List all possible rational zeros f(x)= x^3-5x^2-4x+20

p/q: 20/1 -> 
+-1, +-2, +-4, +-5, +-10, +-20

Find each sum in the same base as the given numerals. Question: 323four + 212four Question: 5374eight + 615eight

323four + 212four = 

3+2 -> 11four (so carry1 keep 1) and leads to

1+2+1 ->10four (so carry 1 keep 0) and leads to

1+3+2 -> 12four 

putting them together: 1201four 

using same strategy: 

5374eight + 615eight = 1354eight

solve for x: x/a - 2x = c

 x/a - 2x = c

x(1/a-2)=c

x(1/a-2a/a)=c

x(1-2a)/a=c
a/(1-2a)x(1-2a)/a=ca/(1-2a)

x=c*a/(1-2a)

factor: x3 - 12x2 + 48x - 64

x3 - 12x2 + 48x - 64 =
x3-64 -12x(x-4)=
(x-4)(x2+4x+16)-12x(x-4)=
(x-4)(x2-8x+16)=
(x-4)3 

:)

Solve: -4/(y+2)=-6+1/(y+1)

 

 

 
 

so y=-3/2 or y=-2/3

Find the exact value by using a half-angle identity. cos(-pi/8)

cosine is an even function so 
 

 

what is 41 3/4 percent as a fraction and also what is 61 1/4 percent as a fraction

41 3/4 percent means 
41.75/100 = 
4175/1000=
(167*25)/(400*25)=
167/400 

61 1/4 percent means 
6125/1000=
(49*125)/(80*125)=
49/80