Make s the subject of the relation: P = S + \(\frac{sm^2}{nr}\)
s = \(\frac{mrp}{nr + m^2}\)
s = \(\frac{nr + m^2}{mrp}\)
s = \(\frac{nrp}{mr + m^2}\)
s = \(\frac{nrp}{nr + m^2}\)
Correct answer is D
P = S + \(\frac{sm^2}{nr}\)
P = S(1 + \(\frac{m^2}{nr}\))
P = S(1 + \(\frac{nr + m^2}{nr}\))
nrp = S(nr + m2)
S = \(\frac{nrp}{nr + m^2}\)
Simplify; \(\frac{2}{1 - x} - \frac{1}{x}\)
\(\frac{x + 1}{x(1 - x)}\)
\(\frac{3x - 1}{ x(1 - x)}\)
\(\frac{3x + 1}{ x(1 - x)}\)
\(\frac{x + 1}{ x(1 - x)}\)
Correct answer is D
\(\frac{2}{1 - x} - \frac{1}{x}\) = \(\frac{2x - 1(1 - x)}{x(1 - x)}\)
= \(\frac{2x - 1(1 + x)}{x(1 - x)}\)
= \(\frac{3x - 1}{x(1 - x)}\)
Given that 2x + y = 7 and 3x - 2y = 3, by how much is 7x greater than 10?
1
3
7
17
Correct answer is C
2x + y = 7...(1)
3x - 2y = 3...(2)
From (1), y = 7 - 2x for y in (2)
3x - 2(7 - 2x) = 3
3x - 14 + 4x = 3
7x + 3 + 14 = 17
x = \(\frac{17}{7}\)
Hence, 7 x \(\frac{17}{7}\)
= 17 - 10
= 7
Find the values of y for which the expression \(\frac{y^2 - 9y + 18}{y^2 + 4y - 21}\) is undefined
6, -7
3, -6
3, -7
-3, -7
Correct answer is C
\(\frac{y^2 - 9y + 18}{y^2 + 4y - 21}\)
Factorize the denominator;
Y2 + 7y - 3y - 21
= y(y + 7) -3 (y + 7)
= (y - 3)(y + 7)
Hence the expression \(\frac{y^2 - 9y + 18}{y^2 + 4y - 21}\) is undefined
when y2 + 4y - 21 = 0
ie. y = 3 or -7
The roots of a quadratic equation are \(\frac{4}{3}\) and -\(\frac{3}{7}\). Find the equation
21x2 - 19x - 12 = 0
21x2 + 37x - 12 = 0
21x2 - x + 12 = 0
21x2 + 7x - 4 = 0
Correct answer is A
Let x = \(\frac{4}{3}\), x = -\(\frac{3}{7}\)
Then 3x = 4, 7x = -3
3x - 4 = 0, 7x + 3 = 0
(3x - 4)(7x + 3) = 0
21x2 + 9x - 28x - 12 = 0
21x2 - 19x - 12 = 0