Question

The number of real solutions of the equation $$\sin \left( {{e^x}} \right) = {5^x} + {5^{ - x}}$$    is

A. 0  
B. 1
C. 2
D. infinitely many
Answer :   0
Solution :
$${5^x} + {5^{ - x}} \geqslant 2\left( {\because \,\,{\text{AM }} \geqslant {\text{ GM}}} \right);\,{\text{but }}\sin {e^x} \leqslant 1.$$

Releted MCQ Question on
Algebra >> Quadratic Equation

Releted Question 1

If $$\ell ,m,n$$  are real, $$\ell \ne m,$$  then the roots by the equation: $$\left( {\ell - m} \right){x^2} - 5\left( {\ell + m} \right)x - 2\left( {\ell - m} \right) = 0$$         are

A. Real and equal
B. Complex
C. Real and unequal
D. None of these
Releted Question 2

The equation $$x + 2y + 2z = 1{\text{ and }}2x + 4y + 4z = 9{\text{ have}}$$

A. Only one solution
B. Only two solutions
C. Infinite number of solutions
D. None of these
Releted Question 3

Let $$a > 0, b > 0$$    and $$c > 0$$ . Then the roots of the equation $$a{x^2} + bx + c = 0$$

A. are real and negative
B. have negative real parts
C. both (A) and (B)
D. none of these
Releted Question 4

Both the roots of the equation $$\left( {x - b} \right)\left( {x - c} \right) + \left( {x - a} \right)\left( {x - c} \right) + \left( {x - a} \right)\left( {x - b} \right) = 0$$           are always

A. positive
B. real
C. negative
D. none of these.

Practice More Releted MCQ Question on
Quadratic Equation


Practice More MCQ Question on Maths Section