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RUN REVIEW · Specialist Mathematics · Units 1 & 2 · Tech-active

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11 Sep 2026, 9:20 p.m.

20Serious score
01 Which response best completes this VCE-style item? The determinant of \(\begin{pmatrix}2&1\\3&4\end{pmatrix}\) is
A 8 This does not satisfy the stated relationship.
B −5 This does not satisfy the stated relationship.
C 11 This does not satisfy the stated relationship.
D 5 2×4−1×3=5.

Written for icaijy.com · U1–2 · Matrices · answered at 100 ms

02 The determinant of \(\begin{pmatrix}2&1\\3&4\end{pmatrix}\) is
A 8 This does not satisfy the stated relationship.
B 11 This does not satisfy the stated relationship.
C 5 2×4−1×3=5.
D −5 This does not satisfy the stated relationship.

Written for icaijy.com · U1–2 · Matrices · answered at 100 ms

03 During a one-minute revision round: The equations \(x+y=5\), \(x-y=1\) have solution
A \((4,1)\) This does not satisfy the stated relationship.
B \((5,0)\) This does not satisfy the stated relationship.
C \((2,3)\) This does not satisfy the stated relationship.
D \((3,2)\) Add the equations to obtain x=3.

Written for icaijy.com · U1–2 · Linear systems · answered at 100 ms

04 A student is checking a worked solution. The angle between (1,0) and (1,1) is
A \(\pi\) This does not satisfy the stated relationship.
B \(\pi/4\) The dot-product cosine is 1/√2.
C \(3\pi/4\) This does not satisfy the stated relationship.
D \(\pi/2\) This does not satisfy the stated relationship.

Written for icaijy.com · U1–2 · Vectors · answered at 100 ms

05 During a one-minute revision round: A complete graph \(K_6\) has how many edges?
A 12 This does not satisfy the stated relationship.
B 15 \(6\times5/2=15\).
C 30 This does not satisfy the stated relationship.
D 6 This does not satisfy the stated relationship.

Written for icaijy.com · U1–2 · Graphs · answered at 100 ms

06 Which response best completes this VCE-style item? A vector calculation returns magnitude −4. The correct interpretation is
A a magnitude cannot be negative, so the setup or output is wrong Magnitude is a non-negative scalar.
B the vector points down This does not satisfy the stated relationship.
C the magnitude is −4 This does not satisfy the stated relationship.
D the vector points left This does not satisfy the stated relationship.

Written for icaijy.com · U1–2 · Modelling · answered at 100 ms

07 If \(u_{n+1}=u_n+3\) and \(u_1=2\), then \(u_5=\)
A 14 Four increments of 3 give 14.
B 15 This does not satisfy the stated relationship.
C 11 This does not satisfy the stated relationship.
D 17 This does not satisfy the stated relationship.

Written for icaijy.com · U1–2 · Recurrence · answered at 100 ms

08 Which response best completes this VCE-style item? For \(\vec a=(1,2,2)\), \(|\vec a|=\)
A \(\sqrt5\) This does not satisfy the stated relationship.
B 3 \(\sqrt{1+4+4}=3\).
C 9 This does not satisfy the stated relationship.
D 5 This does not satisfy the stated relationship.

Written for icaijy.com · U1–2 · Vectors · answered at 100 ms

09 During a one-minute revision round: If \(u_{n+1}=u_n+3\) and \(u_1=2\), then \(u_5=\)
A 11 This does not satisfy the stated relationship.
B 15 This does not satisfy the stated relationship.
C 17 This does not satisfy the stated relationship.
D 14 Four increments of 3 give 14.

Written for icaijy.com · U1–2 · Recurrence · answered at 100 ms

10 During a one-minute revision round: The angle between (1,0) and (1,1) is
A \(\pi/2\) This does not satisfy the stated relationship.
B \(\pi/4\) The dot-product cosine is 1/√2.
C \(\pi\) This does not satisfy the stated relationship.
D \(3\pi/4\) This does not satisfy the stated relationship.

Written for icaijy.com · U1–2 · Vectors · answered at 100 ms

11 During a one-minute revision round: One Newton step for \(f(x)=x^2-2\) from \(x_0=1.5\) gives
A approximately 1.2500 This does not satisfy the stated relationship.
B approximately 1.4167 \(x_1=x_0-f(x_0)/f\prime(x_0)\).
C approximately 1.5000 This does not satisfy the stated relationship.
D approximately 2.0000 This does not satisfy the stated relationship.

Written for icaijy.com · U1–2 · Numerical methods · answered at 100 ms

12 A vector calculation returns magnitude −4. The correct interpretation is
A the vector points down This does not satisfy the stated relationship.
B the vector points left This does not satisfy the stated relationship.
C a magnitude cannot be negative, so the setup or output is wrong Magnitude is a non-negative scalar.
D the magnitude is −4 This does not satisfy the stated relationship.

Written for icaijy.com · U1–2 · Modelling · answered at 100 ms

13 The angle between (1,0) and (1,1) is
A \(3\pi/4\) This does not satisfy the stated relationship.
B \(\pi\) This does not satisfy the stated relationship.
C \(\pi/2\) This does not satisfy the stated relationship.
D \(\pi/4\) The dot-product cosine is 1/√2.

Written for icaijy.com · U1–2 · Vectors · answered at 100 ms

14 During a one-minute revision round: \((2+i)(3-i)=\)
A \(6-i\) This does not satisfy the stated relationship.
B \(7-i\) This does not satisfy the stated relationship.
C \(7+i\) Expand and use i²=−1.
D \(5-i\) This does not satisfy the stated relationship.

Written for icaijy.com · U1–2 · Complex arithmetic · answered at 100 ms

15 A student is checking a worked solution. For \(\vec a=(1,2,2)\), \(|\vec a|=\)
A 5 This does not satisfy the stated relationship.
B 9 This does not satisfy the stated relationship.
C 3 \(\sqrt{1+4+4}=3\).
D \(\sqrt5\) This does not satisfy the stated relationship.

Written for icaijy.com · U1–2 · Vectors · answered at 100 ms

16 During a one-minute revision round: \(\binom{8}{2}=\)
A 56 This does not satisfy the stated relationship.
B 28 8×7/2=28.
C 16 This does not satisfy the stated relationship.
D 64 This does not satisfy the stated relationship.

Written for icaijy.com · U1–2 · Counting · answered at 100 ms

17 A student is checking a worked solution. The equations \(x+y=5\), \(x-y=1\) have solution
A \((5,0)\) This does not satisfy the stated relationship.
B \((4,1)\) This does not satisfy the stated relationship.
C \((2,3)\) This does not satisfy the stated relationship.
D \((3,2)\) Add the equations to obtain x=3.

Written for icaijy.com · U1–2 · Linear systems · answered at 100 ms

18 The equations \(x+y=5\), \(x-y=1\) have solution
A \((5,0)\) This does not satisfy the stated relationship.
B \((3,2)\) Add the equations to obtain x=3.
C \((2,3)\) This does not satisfy the stated relationship.
D \((4,1)\) This does not satisfy the stated relationship.

Written for icaijy.com · U1–2 · Linear systems · answered at 100 ms

19 During a one-minute revision round: A geometric sequence has first term 3 and ratio 2. Its sixth term is
A 64 This does not satisfy the stated relationship.
B 48 This does not satisfy the stated relationship.
C 96 3×2⁵=96.
D 192 This does not satisfy the stated relationship.

Written for icaijy.com · U1–2 · Sequences · answered at 100 ms

20 Testing 10 000 cases with CAS establishes a universal integer claim
A whenever no counterexample appears This does not satisfy the stated relationship.
B only if paired with a valid general proof Finite checking alone does not prove an infinite claim.
C only for prime inputs This does not satisfy the stated relationship.
D with certainty by itself This does not satisfy the stated relationship.

Written for icaijy.com · U1–2 · Proof checking · answered at 100 ms

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