Nas equacoes do segundo grau: x ao quadrado +9=0 e x ao quadrado menos 3x=0 i as duas equacoes possuem raizes reais ii apenas uma das equacoes pode ser resolvida no conjunto dos numeros reais iii nenhuma das equacoes tem solucao no conjunto dos numeros reais iv para obter a solucao de uma das equacoes é preciso recorrer ao conjunto dos numeros complexos. quais dessas sao corretas?

Do social recommendations increase ad effectiveness? a study of online video viewers compared viewers who arrived at an advertising video for a particular brand by following a social media recommendation link to viewers who arrived at the same video by web browsing. data were collected on whether the viewer could correctly recall the brand being advertised after seeing the video. the results are given below.correctly recalled the brandarrival 409153browsing20484b. conduct the hypothesis test, using the 0.025 level of significance.what is the value of the test statistic? χ2stat=what is the p-value? p-value=is this value significant atα=0.025?

Acompany manufactures three types of cabinets. it makes 110 cabinets each week. in the first week, the sum of the number of type-1 cabinets and twice the number of type-2 cabinets produced was 10 more than the number of type-3 cabinets produced. the next week, the number of type-1 cabinets produced was three times more than in the first week, no type-2 cabinets were produced, and the number of type-3 cabinets produced was the same as in the previous week.

Which of the following represents the factorization of the trinomial below? x^2+7x-30