Questions

True False[1 Marks ]

Take a timed test

6 questions · self-marked practice — reveal the answer and mark yourself.

Question 11 Mark
Write whether the following statements are true or false. Justify your answers.
Every quadratic equations has at most two roots.
Answer
Consider the quadratic equation $x^2-5 x+6=0$. put 2 and 3 in $x$ and the quadratic expression $x^2-5 x+6$ becomes equal to 0 . So, 2 and 3 are the roots of the quadratic equation $x^2-5 x+6=0$. So, any quadratic equation can have atmost two roots i.e., one or two roots, but not more than two.
View full question & answer
Question 21 Mark
Write whether the following statements are true or false. Justify your answers.
Every quadratic equation has at least one real root.
Answer
False:
Consider a quadratic equation $x^2+1=0$ which has no real root. So, the given statement is false.
View full question & answer
Question 31 Mark
Write whether the following statements are true or false. Justify your answers.
If the coefficient of $x^2$ and the constant term have the same sign and if the coefficient of x term is zero, then the quadratic equation has no real roots.
Answer
True:
In quadratic equation $a x^2+b x+c=0$, if $a$ and $c$ have same sign and $b=0$, then $b^2-4 a c=(0)^2-4 a c=-4 a c<0$.So, the quadratic equation has no real roots.
Hence, the given statement is true.
View full question & answer
Question 41 Mark
Write whether the following statements are true or false. Justify your answers.
If the coefficient of $x^2$ and the constant term of a quadratic equation have opposite signs, then the quadratic equation has real roots.
Answer
True:
In quadratic equation $a x^2+b x+c=0$, if a and $c$ have opposite signs, then $a c<0$. Therefore, $b ^2-4 ac >0$. So, the quadratic equation has real roots. Hence, the given statement is true.
View full question & answer
Question 51 Mark
Write whether the following statements are true or false. Justify your answers.
Every quadratic equation has at least two roots.
Answer
False:
Consider the quadratic equation $x^2-4 x+4=0$ which has only 2 as root. So, the given statement is false.
View full question & answer
Question 61 Mark
Write whether the following statements are true or false. Justify your answers.
Every quadratic equation has exactly one root.
Answer
False:
Consider a quadratic equation $x^2-4=0$ which has two distinct roots -2 and 2 . So, the given statement is false.
View full question & answer
True False[1 Marks ] - Maths STD 10 Questions - Vidyadip