Why isn't the answer to TMUA-P1-MM2-006 shown upfront?

The options are lettered without marking the correct one so you attempt TMUA-P1-MM2-006 first — TMUA questions reward spotting the trap before you check the worked solution below.

Do I need a calculator for TMUA-P1-MM2-006?

No — calculators are banned in the TMUA. TMUA-P1-MM2-006 is set for a no-calculator target of about 180 seconds; the worked solution shows the fastest by-hand route.

Which TMUA specification point is TMUA-P1-MM2-006?

TMUA-P1-MM2-006 is Paper P1 · Sequences and series (specification code MM2), level 2. Drill more of the same topic from this page.

TMUA-P1-MM2-006 — Paper P1 · Sequences and series · Level 2

P1MM2Level 2~180s target

Spec: MM2 · No calculator · ~180s

A sequence is defined by

u_1 = 5

and

u_{n+1} = 2u_n - 3

. What is the value of

u_3

Options

$7$
$10$
$11$
$13$
$17$

Letters only — the answer key is hidden. Work it out, then check the solution below.

Hint (check trope)

No written hint yet — check the trope: recurrence-iteration, dropped-constant. Name the trap first, work the stem by hand, then open the solution below.

Show solution

Apply the rule twice:

u_2 = 2(5) - 3 = 7

, then

u_3 = 2(7) - 3 = 11

. Trap:

10

doubles without subtracting — plausible if you skim the recurrence.

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Same topic · same level

P1MM2Level 2

TMUA-P1-MM2-007

An arithmetic series has first term 2 and common difference 5. What is the sum of its first 20 terms?

Sequences and series

Open TMUA-P1-MM2-007 →

Step up a level

P1MM2Level 3

TMUA-P1-MM2-012

An arithmetic series has first term 7 and common difference 4. What is the smallest n such that the sum of the first n t…

Sequences and series

Open TMUA-P1-MM2-012 →

TMUA-P1-MM2-006 — Paper P1 · Sequences and series · Level 2

Options

Keep practising

Master Sequences and series

TMUA-P1-MM2-006 — Paper P1 · Sequences and series · Level 2

Options

Keep practising

Master Sequences and series