Given that \(81\times 2^{2n-2} = K, find \sqrt{K}\)
\(4.5\times 2^{n}\)
\(4.5\times 2^{2n}\)
\(9\times 2^{n-1}\)
\(9\times 2^{2n}\)
Correct answer is C
\(K = 81 \times 2^{2n - 2}\)
\(\sqrt{K} = \sqrt{81 \times 2^{2n - 2}}\)
= \(9 \times 2^{n - 1}\)
If \(y = \sqrt{ax-b}\) express x in terms of y, a and b
\(x = \frac{y^2-b}{a}\)
\(x = \frac{y+b}{a}\)
\(x = \frac{y-b}{a}\)
\(x = \frac{y^2 + b}{a}\)
Correct answer is D
\(y = \sqrt{ax-b}\)
\(y^2 = ax-b\)
\(y^2 +b = ax\)
\(x = \frac{y^2 + b}{a}\)
Simplify \(\frac{2-18m^2}{1+3m}\)
\(2(1+3m)\)
\(2(1+3m^2)\)
\(2(1-3m)\)
\(2(1-3m^2)\)
Correct answer is C
\(\frac{2-18m^2}{1+3m}=\frac{2(1-(3m)^2)}{1+3m}\)
\(frac{2(1-(3m)(1+3m)}{1+3m}=2(1-3m)\)
Given that m = -3 and n = 2 find the value of \(\frac{3n^2 - 2m^3}{m}\)
-22
-14
14
22
Correct answer is A
Given that m = -3, n = 2, the value of
\(\frac{3n^2 - 2n^3}{m}\\
\frac{3(2)^2 -2(-3)^2}{-3}= \frac{12+54}{-3}=-22\)
In the diagram, POR is a circle with center O. ∠QPR = 50°, ∠PQO = 30° and ∠ORP = m. Find m.
20o
25o
30o
50o
Correct answer is A
< QOR = 50° x 2 = 100°
Reflex < QOR = 360° - 100° = 260°
\(\therefore\) 30° + 50° + 260° + m = (4 - 2) x 180°
340° + m = 360°
m = 360° - 340° = 20°
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