weekly test math physics

If one of the zeros of the quadratic polynomial x²+3x+k is 2, then the value of k is

• 10

• -10

• -7

• -2

The total number of factors of a prime number is

• 1

• 0

• 3

• 2

The quadratic polynomial, the sum of whose zeros is -5 and their product is 6, is

• x²+5x+6

• x²-5x+6

• x²-5x-6

• -x²+5x+6

The HCF and the LCM of 12,21,15 respectively are

• 2,140

• 13,420

• 3,420

• 420,3

Has the rational number 441/(2². 5⁷. 7² ) a terminating or a non terminating decimal representation

• Terminating

• nonterminating

• both

• none of them

If α, β are the zeroes of a polynomial, such that α+β=6 and αβ=4, then write the polynomial.

• x²-6x+4

• x²-4x+6

• x²+6x-4

• x²+6x+4

If two zeroes of the polynomial x³-4x²-3x+12 are √3 and√3, then find its third zero

• 2

• 4

• -4

• -2

A student obtained a sharp inverted image of a distant tree on a screen placed in front of the concave mirror. He then removed the screen and tried to look into the mirror. He would now see

• a very blurred image on the wall opposite to the mirror

• an erect and magnified image of the tree in the mirror

• no image as the screen has been removed

• a highly diminished inverted image of the tree at the focus of the mirror

A student has to determine the focal length of a concave mirror by obtaining the image of a distant object on a screen. For getting best result he should focus

• a distant tree or an electric pole

• a well-illuminated distant building

• well-lit grills of the nearest window

• a burning candle placed at the distant edge of the laboratory table