The parametric equations of a line are given below - HSC - SSCE Mathematics Extension 1 - Question 11 - 2023 - Paper 1
Question 11
The parametric equations of a line are given below.
$x = 1 + 3t$
$y = 4t$
Find the Cartesian equation of this line in the form $y = mx + c$.
In how many dif... show full transcript
Worked Solution & Example Answer:The parametric equations of a line are given below - HSC - SSCE Mathematics Extension 1 - Question 11 - 2023 - Paper 1
Step 1
The parametric equations of a line are given below. Find the Cartesian equation of this line in the form y = mx + c.
96%
114 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
To eliminate the parameter t, we can express t in terms of x using the first equation:
From x=1+3t, we have:
t=3x−1
Now, substitute t in the second equation for y:
y=4t=4(3x−1)=34(x−1)=34x−4
Rearranging gives:
y=34x−34
Thus, the Cartesian equation is y=34x−34.
Step 2
In how many different ways can all the letters of the word CONDOBOLIN be arranged in a line?
99%
104 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The word CONDOBOLIN has 12 letters in total with some repetitions:
C: 1
O: 2
N: 2
D: 1
B: 1
L: 1
I: 1
Using the formula for permutations of multiset:
extTotalarrangements=n1!⋅n2!⋯nk!n!
Substituting the values:
extTotalarrangements=2!⋅2!⋅1!⋅1!⋅1!⋅1!⋅1!12!
Calculating gives:
=4479001600=119750400
Therefore, the total number of arrangements is 119750400.
Step 3
Consider the polynomial P(x) = x^3 + ax^2 + bx - 12, where a and b are real numbers. Find a and b.
96%
101 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
Using the factor theorem, since x+1 is a factor:
Evaluate P(−1):
P(−1)=(−1)3+a(−1)2+b(−1)−12=−1+a−b−12=0a - b - 13 = 0 \\ \Rightarrow a - b = 13 \tag{1}
Using the remainder theorem, since the remainder when divided by x−2 is -18:
2. Evaluate P(2):
P(2)=(2)3+a(2)2+b(2)−12=8+4a+2b−12=−18
Simplifying gives:
4a + 2b - 4 = -18 \\ \Rightarrow 4a + 2b = -14 \\ \Rightarrow 2a + b = -7 \tag{2}
Now, solve equations (1) and (2) together:
From (1): ( b = a - 13 \ ext{Substituting into (2):})
3a - 13 = -7 \\ \Rightarrow 3a = 6 \\ \Rightarrow a = 2$$