Ncert Solutions Maths class 11th

Let $A,B,C$ and $D$ be four non - empty sets. The contrapositive statement of "If $A\subseteq B$ and $B\subseteq D$ , then $A\subseteq C$  " is:

Let the tangents drawn from the origin to the circle, $x^2+y^2-8x-4y+16=0$ touch it at the points $A$ and $B$ . Then $(AB{)}^2$  is equal to:

The locus of a point which divides the line segment joining the point $(0,-1)$ $$ and a point on the parabola, $x^2=4y$ ${}^{}$ , internally in the ratio $1:2$ $$ , is

If $\frac{3+\mathrm{i}\mathrm{s}\mathrm{i}\mathrm{n}\theta }{4-\mathrm{i}\mathrm{c}\mathrm{o}\mathrm{s}\theta },\theta \in \left[\mathrm{0,2}\pi \right]$ , is a real number, then an argument of $\mathrm{s}\mathrm{i}\mathrm{n}?\theta +\mathrm{i}\mathrm{c}\mathrm{o}\mathrm{s}?\theta$  is:

If the line y=mx+c is a common tangent to the hyperbola x²/100 - y²/64 = 1 and the circle x²+y²=36, then which one of the following is true?

Let $\alpha$ and $\beta$ be the roots of the equation $x^2-x-1=0$ . If $P_k=(\alpha {)}^k+(\beta {)}^k,k\ge 1$ , then which one of the following statements is not true?

If the sum of the first 20 terms of the series log₇(₁/₂)x + log₇(₁/₃)x + log₇(₁/₄)x + . is 460, then x is equal to:

Let $a_1,a_2,a_3,\dots \dots$ . be a G.P. such that $a_1<0,a_1+a_2=4$ and $a_3+a_4=16$ . If ${\sum }_{i=1}^9 a_i=4\lambda$ , then $\lambda$ is equal to:

There are 3 sections in a question paper and each section contains 5 questions. A candidate has to answer a total of 5 questions, choosing at least one question from each section. Then the number of ways, in which the candidate can choose the questions, is:

The locus of the mid - points of the perpendiculars drawn from points on the line, $x=2y$ to the line $x=y$ is: