The factorial ! just means we multiply by every natural number less that the value so
6! =6×5×4×3×2×1= 720
for permutations we use the formula n!/(n-r)!
so we have 8!/(8-5)!=8!/3!=8×7×6×5×4
for combinations s we have n!/(n-r)!r!
so we have 12!/(12-4)!4!=12!/8!4!=12×11×10×9/4×3×2=11×10×9/2=99×5
Answer:
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Step-by-step explanation:
Answer:
Step-by-step explanation:
(x+3)² -5 =0 , use the formula (a+b) ² = a²+b²+2ab
x²+9 +6x -5 =0 , combine like terms
x²+6x +4 =0, use the quadratic formula x = (-b±√b²-4ac)/2a
x= (-6 ±√6²-4*1*4)/2*1
x= (-6 ± √36-16) /2
x= (-6±√20)/2
x=(-6 +2√5)/2 and x=( -6-2√5) /2, factor 2 in the numerator and simplify
x= -3 +√5 and x= -3 -√5
X/3 +4 = 5+x/6
6(x/3 +4 = 5+x/6)
2x+ 24 = 30 +x
x= 6
(b) one-sample t-test for a population mean
ur welcome :D
