3 sec
2 sec
4 sec
1 sec
Correct answer is A
u=27ms−1;a=−9ms−2;v=0;t=?
v=u+at;t=v−ua
t=0−27−9=−27−9
∴
Given that M is the midpoint of T (2, 4) and Q (-8, 6), find the length of MQ .
√26 units
√28 units
√24 units
√30 units
Correct answer is A
|MQ| = \frac{1}{2} |TQ|
|TQ| = √((y2 - y1)^2 + (x2 - x1)^2)
|TQ| = √((6 - 4)^2 + (-8 - 2)^2)
|TQ| = √(2^2 + (-10)^2)
|TQ| = √(4 + 100) = √104
|TQ| = 2√26 units
|MQ| = \frac{1}{2} |TQ| = 2 \times 2√26
∴ |MQ| = √26 units
Find the radius of the circle 2x^2 + 2y^2 - 4x + 5y + 1 = 0
\frac{\sqrt33}{4}
\frac{\sqrt5}{6}
\frac{5}{6}
\frac{33}{4}
Correct answer is A
Standard Form equation of a circle (Center-Radius Form): (x − a)^2 + (y − b)^2 = r^2
Where "a" and "b" are the coordinates of the center and "r" is the radius of the circle
2x^2+2y^2-4x+5y+1=0
Divide through by 2
= x^2+y^2-2x+\frac{5}{2}y+\frac{1}{2}= 0
=x^2-2x+y^2+\frac{5}{ 2}y=-\frac{1}{ 2}
=x^2-2x+1^2+y^2+\frac{5}{ 2}y+(\frac{5}{ 4})^2-1-\frac{25}{16}=-\frac{1}{2}
=(x-1)^2+(y+\frac{5}{4})^2=-\frac{1}{2}+1+\frac{25}{16}
=(x-1)^2+(y-(-\frac{5}{4}))^2=\frac{33}{16}
=(x-1)^2+(y-(-\frac{5}{4}))^2=(\frac{\sqrt33}{4})^2
\therefore a = 1, b = - \frac{5}{4} and r \frac{\sqrt33}{4} (answer)
The table shows the operation * on the set {x, y, z, w}.
* | X | Y | Z | W |
X | Y | Z | X | W |
Y | Z | W | Y | X |
Z | X | Y | Z | W |
W | W | X | W | Z |
Find the identity of the element.
W
Y
Z
X
Correct answer is C
From the table, x * z = x, y * z = y, z * z = z and w * z = w
∴ z is the identity element
If(\frac{1}{9})^{2x-1} = (\frac{1}{81})^{2-3x}find the value of x
-\frac{5}{8}
-\frac{3}{4}
\frac{3}{4}
-\frac{5}{8}
Correct answer is D
(\frac{1}{9})^{2x-1} = (\frac{1}{81})^{2-3x}
(\frac{1}{9})^{2x-1} = (\frac{1}{9})^{2(2-3x)}
(\frac{1}{9})^{2x-1} = (\frac{1}{9})^{4-6x}
Since the bases are equal, powers can be equated
= 2x - 1 = 4 - 6x
= 2x + 6x = 4 + 1
= 8x = 5
\therefore x = \frac{5}{8}