What is the solution set of the quadratic inequality 6x²+1≤0?
a) {x|x∈r}
b) {x|x=-1/6}
c) ∅
d) {x|x=1/6}

Complex numbers multiply √-4 * √-25 and show all intermediate steps. alternative notation is sqrt(-4) * sqrt(-25).

Atextile fiber manufacturer is investigating a new drapery yarn, which the company claims has a mean thread elongation of 12 kilograms with a standard deviation of 0.5 kilograms. the company wishes to test the hypothesis upper h subscript 0 baseline colon mu equals 12 against upper h subscript 1 baseline colon mu less-than 12 using a random sample of n equals 4 specimens. calculate the p-value if the observed statistic is x overbar equals 11.8. round your final answer to five decimal places (e.g. 98.76543).

Cos^2x+cos^2(120°+x)+cos^2(120°-x)i need this asap. pls me