# Recent questions and answers in JEEMAIN PAST PAPERS

### If the equation $x^2 + 2x + 3 = 0$ and $ax^2 + bx + c = 0, a, b, c \in R$, have a common root, then a : b : c$is ### The$z$is a complex number of unit modulus an argument$\theta$, then$arg \begin{pmatrix}\frac{1+z}{1+ \overline{z}} \end{pmatrix}$equals ### A multiple choice examination has 5 questions. Each question has three alternative answers of which exactly one is correct. The probability that a student will get 4 or more correct answers just by guessing is ### 10.6 g of a substance of molecular weight 106 was dissolved in 100 mL. 10 mL of this solution was pipetted out into a 1000 mL flask and made up to the mark with distilled water. The molarity of the resulting solution is : ### If the vectors$\overrightarrow{a} = ( 1, x, -2)$and$\overrightarrow{b} = (x, 3, -4)$are mutually perpendicular, then is : ### If$|\overrightarrow{a}| = 5, |\overrightarrow{b} |= 6, |\overrightarrow{a}. \overrightarrow{b} | = 24$then$|\overrightarrow{a} \times \overrightarrow{b} |$is equal to : ### If$\overrightarrow{\alpha}$and$\overrightarrow{\beta}$are non zero and different vector such that$|\overrightarrow{\alpha} + \overrightarrow{\beta}| = |\overrightarrow{\beta} - \overrightarrow{\alpha}|$, then the angle between$\overrightarrow{\alpha} $and$\overrightarrow{\beta}\$ is :

To see more, click for all the questions in this category.