If \(w=2y^3-1\), what is the value of \(y\) when \(w=13\)?
- \(\dfrac{\sqrt[3]{14}}{2}\)
- \(\sqrt[3]{6}\)
- \(\sqrt[3]{7}\)
- \(\sqrt[3]{14}\)
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If \(w=2y^3-1\), what is the value of \(y\) when \(w=13\)?
\(C\)
\(\text{When}\ w=13:\)
| \(w\) | \(=2y^3-1\) |
| \(13\) | \(=2y^3-1\) |
| \(2y^3\) | \(=14\) |
| \(y^3\) | \(=\dfrac{14}{2}=7\) |
| \(y\) | \(=\sqrt[3]{7}\) |
\(\Rightarrow C\)
Consider the formula \( n=\dfrac{m-p}{q} \).
Which of the following correctly shows \( p \) as the subject of the formula?
\(B\)
| \(n\) | \(=\dfrac{m-p}{q}\) | |
| \(nq\) | \(=m-p\) | |
| \(p\) | \(=m-nq\) |
\(\Rightarrow B\)
Consider the formula \(s=w t+\dfrac{p}{2}\).
Which of the following correctly shows \(p\) as the subject of the formula?
\(D\)
| \(s\) | \(=w t+\dfrac{p}{2}\) | |
| \(\dfrac{p}{2}\) | \(=s-w t\) | |
| \(p\) | \(=2(s-w t)\) | |
| \(=2s-2w t\) |
\(\Rightarrow D\)
Given the formula `C = (A(y + 1))/24`, calculate the value of `y` when `C = 120` and `A = 500`. (3 marks)
--- 6 WORK AREA LINES (style=lined) ---
`4.76`
`text(Make)\ \ y\ \ text(the subject:)`
| `C` | `= (A(y + 1))/24` |
| `24C` | `= A(y + 1)` |
| `y + 1` | `= (24C)/A` |
| `y` | `= (24C)/A-1` |
| `= (24 xx 120)/500-1` | |
| `= 4.76` |
Which of the following correctly expresses `x` as the subject of `y=(ax-b)/(2)` ?
`A`
| `y` | `=(ax-b)/(2)` | |
| `2y` | `=ax-b` | |
| `ax` | `=2y+b` | |
| `:.x` | `=(2y+b)/a` |
`=>A`
Make `F` the subject of the equation `C = 5/9(F - 32)`. (2 marks)
`F = (9C)/5 + 32`
| `C` | `= 5/9(F – 32)` |
| `9C` | `= 5(F – 32)` |
| `(9C)/5` | `= F – 32` |
| `:.F` | `= (9C)/5 + 32` |
Make `r` the subject of the equation `V = 4/3 pir^3`. (3 marks)
--- 6 WORK AREA LINES (style=lined) ---
`r = root(3)((3V)/(4pi))`
| `V` | `= 4/3 pir^3` |
| `3V` | `=4pir^3` |
| `(3V)/4` | `= pir^3` |
| `r^3` | `= (3V)/(4pi)` |
| `r` | `= root(3)((3V)/(4pi))` |
Which of the following correctly expresses `y` as the subject of the formula `3x-4y-1 = 0`?
`C`
| `3x-4y-1` | `= 0` |
| `4y` | `= 3x-1` |
| `:. y` | `= (3x-1)/4` |
`=> C`
Make `p` the subject of the equation `c = 5/3p + 15`. (2 marks)
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`p = 3/5 c-9`
| `c` | `= 5/3p + 15` |
| `5/3p` | `= c-15` |
| `p` | `= 3/5 (c-15)` |
| `= 3/5 c-9` |
Make `y` the subject of the equation `x = sqrt(yp-1)`. (2 marks)
`y = (x^2 + 1)/p`
| `x` | `= sqrt(yp-1)` |
| `yp-1` | `= x^2` |
| `yp` | `= x^2 + 1` |
| `:. y` | `= (x^2 + 1)/p` |
Which of the following correctly expresses `Q` as the subject of `e = iR + Q/C`?
`=> B`
| `e` | `= iR + Q/C` |
| `Q/C` | `= e-iR` |
| `:. Q` | `= C(e-iR)` |
| `= Ce-CiR` |
`=> B`
The volume of a sphere is given by `V = 4/3 pi r^3` where `r` is the radius of the sphere.
If the volume of a sphere is `\text{220 cm}^3`, find the radius, to 1 decimal place. (3 marks)
--- 6 WORK AREA LINES (style=lined) ---
`3.7\ \ text{cm (to 1 d.p.)}`
| `V` | `= 4/3 pi r^3` |
| `3V` | `= 4 pi r^3` |
| `r^3` | `= (3V)/(4 pi)` |
`text(When)\ \ V = 220`
| `r^3` | `= (3 xx 220)/(4 pi)` |
| `= 52.521…` | |
| `:. r` | `=root3 (52.521…)` |
| `= 3.744…\ \ \ text{(by calc)}` | |
| `= 3.7\ \ text{cm (to 1 d.p.)}` |
The formula `C = 5/9 (F-32)` is used to convert temperatures between degrees Fahrenheit `(F)` and degrees Celsius `(C)`.
Convert 3°C to the equivalent temperature in Fahrenheit. (2 marks)
--- 5 WORK AREA LINES (style=lined) ---
`37.4\ text(degrees)\ F`
| `C` | `= 5/9(F-32)` |
| `F-32` | `= 9/5C` |
| `F` | `= 9/5C + 32` |
`text(When)\ \ C = 3,`
| `F` | `= (9/5 xx 3) + 32` |
| `= 37.4\ text(degrees)\ F` |
Make `L` the subject of the equation `T = 2piL^2`. (2 marks)
--- 4 WORK AREA LINES (style=lined) ---
`± sqrt(T/(2pi))`
| `T` | `= 2piL^2` |
| `L^2` | `= T/(2pi)` |
| `:.L` | `= ±sqrt(T/(2pi))` |
What is the formula for `q` as the subject of `4p =5t + 2q^2`?
`D`
| `4p` | `= 5t + 2q^2` |
| `2q^2` | `= 4p – 5t` |
| `q^2` | `= (4p – 5t)/2` |
| `q` | `= +- sqrt{(4p – 5t)/2}` |
`=> D`
If `d = 6t^2`, what is a possible value of `t` when `d = 2400`?
`B`
| `d` | `= 6t^2` |
| `t^2` | `= d/6` |
| `t` | `= +- sqrt(d/6)` |
`text(When)\ \ d = 2400:`
| `t` | `= +- sqrt(2400/6)` |
| `= +- 20` |
`=> B`
Which of the following correctly expresses `T` as the subject of `B = 2pi (R + T/2)`?
`A`
| `B` | `= 2pi (R + T/2)` |
| `B/(2pi)` | `= R + T/2` |
| `T/2` | `= B/(2pi)-R` |
| `T` | `= B/pi-2R` |
`=> A`
Which of the following correctly express `x` as the subject of `a=(nx)/5` ?
`B`
| `a` | `=(nx)/5` |
| `nx` | `=5a` |
| `x` | `=(5a)/n` |
`=> B`
Which of the following correctly expresses `a` as the subject of `s= ut+1/2at^2 `?
`A`
| `s` | `=ut+1/2at^2` |
| `1/2at^2` | `=s-ut` |
| `at^2` | `=2(s-ut)` |
| `a` | `=(2(s-ut))/t^2` |
`=>A`
Which of the following correctly expresses `c` as the subject of `E = mc^2 + p` ?
`A`
| `E` | `=\ mc^2 + p` |
| `mc^2` | `=\ E-p` |
| `c^2` | `=(E-p)/m` |
| `:.c` | `= +-sqrt((E-p)/m)` |
`=> A`
Which equation correctly shows `r` as the subject of `S=800(1-r)`?
`A`
| `S` | `=800(1-r)` |
| `1-r` | `=S/800` |
| `r` | `=1-S/800` |
| `=(800-S)/800` |
`=>\ A`