EASY
Earn 100

Mention the following quadratic equation has real roots or no real roots.
2x2+x+4=0

100% studentsanswered this correctly

Important Questions on Quadratic Equations

HARD
Suppose the quadratic polynomial Px=ax2+bx+c has positive coefficients a, b, c  in arithmetic progression in that order. If Px=0 has integer roots α and β, then α+β+αβ equals
MEDIUM
If sinα and cosα are the roots of the equation ax2+bx+c=0 , then
HARD
Let fx=px2+qx+r , where p, q, r are constants and p0. If f5=-3f2 and f-4=0 , then the other root of f is
MEDIUM
If 1α,1β  are the roots of the equation ax2+bx+1=0, a0, a,bR, then the equation xx+b3+a3-3abx=0 has roots:
EASY
If λ be the ratio of the roots of the quadratic equation in x, 3m2x2+mm-4x+2=0, then the least value of m for which λ+1λ=1, is :
MEDIUM
The number of ordered pairs x, y of real numbers that satisfy the simultaneous equations x+y2=x2+y=12 is
MEDIUM
If αβ, α2=5 α-3, β2=5β-3 , then the equation having αβ and βα as its roots is
MEDIUM
The sum of the solutions of the equation x-2+xx-4+2=0,x>0  is equal to
EASY
If the difference between the roots of the equation x2+kx+1=0 is strictly less than 5, where k2, then k can be any element of the interval
EASY
Let p,q and r be real numbers pq,r0, such that the roots of the equation 1x+p+1x+q=1r are equal in magnitude but opposite in sign, then the sum of squares of these roots is equal to
MEDIUM
The equation 3x2+x+5=x-3, where x  is real, has
HARD
A train travels at a certain average speed for a distance of 63 km and then travels at a distance of 72 km at an average speed of 6 km/hr more than its original speed. If it takes 3 hours to complete total journey, what is the original average speed (km/hr?
HARD
Let S be the set of all non-zero real numbers α such that the quadratic equation αx2-x+α=0 has two distinct real roots x1 & x2 satisfying the inequality x1-x2<1. Which of the following intervals is(are) a subset(s) of S?
MEDIUM
The sum of all the real values of x Satisfying the equation 2x-1x2+5x-50=1 is:
MEDIUM
If m is chosen in the quadratic equation m2+1x2-3x+m2+12=0 such that the sum of its roots is greatest, then the absolute difference of the cubes of its roots is:
MEDIUM
Let α and β be two real roots of the equation k+1tan2x-2λtanx=1-k, where k-1 and λ are real numbers. If tan2α+β=50, then a value of λ is
MEDIUM
If α and β are the roots of the quadratic equation x2+xsinθ-2sinθ=0, θ0,π2 , then α12+β12(α-12+β-12).(α-β)24 is equal to :
MEDIUM

Let a,b be non-zero real numbers. Which of the following statements about the quadratic equation ax2+a+bx+b=0 is necessarily true ?

I It has at least one negative root.

II It has at least one positive root.

III Both its roots are real.

EASY
The harmonic mean of the roots of the equation 5+2x2-4+5x+8+25=0 is
HARD

A motorboat whose speed is 18 km/h in still water takes 1 hour more to go 24 km upstream than to return downstream to the same spot. Find the speed of the stream.