CBSE 12TH MATHEMATICS - Online Test
Q1. In a LPP, the linear inequalities or restrictions on the variables are called
Answer : Option C
Explaination / Solution:
In a LPP, the linear inequalities or restrictions on the variables are called Linear constraints.
Q2. The range of the function f(x) = x – [x] is
Answer : Option C
Explaination / Solution:
Since [x] ≤ x, therefore , x – [x] ≥ 0. Also, x – [x] <1,∴0⩽x−[x]<1. Therefore ,Range of f = [0,1).
Q3. If is the identity matrix of order 3 , then is
Answer : Option C
Explaination / Solution:
Because , the inverse of an identity matrix is an identity matrix itself.
Q4.
The area bounded by the angle bisectors of the lines
Answer : Option B
Explaination / Solution:
The angle bisectors of the line given by are x = 0 , y = 1. Required area : =
Q5. If a unit vector makes angles , then the components of are
Answer : Option D
Explaination / Solution:
Let,, then ,
Putting these values in (1) , we get :
Putting these values in (1) , we get :
Q7. 4tan−1(15)−tan−1(1239)=
Answer : Option C
Explaination / Solution:
Q8. The system of equations, x + y + z = 6, x + 2 y + 3 z = 14, x + 3 y + 5z = 20 has
Answer : Option A
Explaination / Solution:
The given system of equations does not has a solution if :
Q9.
Derivative of
Answer : Option A
Explaination / Solution:
then ,
Q10. Equation of a plane perpendicular to a given line with direction ratios A, B, C and passing through a given point (x1, y1, z1) is
Answer : Option B
Explaination / Solution:
In Cartesian co – ordinate system Equation of a plane perpendicular to a given line with direction ratios A, B, C and passing through a given point (x1, y1, z1) is given by : A (x – x1) + B (y – y1) + C (z – z1) = 0 .
