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Before the midterm

Misreading a standard trigonometric value

The habit: Check sin and cos at the standard angles on the unit circle before substituting.

6 practice questions are built to catch it, in 5 topics.

Practise against it: 5 questions

What it looks like

A question from implicit differentiation and inverse trigonometric functions, with the answer this slip gives beside the right one.

Introductory1 mark · 2 min

Find the exact value of arcsin⁡ ⁣(sin⁡5π6)\arcsin\!\left(\sin\dfrac{5\pi}{6}\right).

With the slip
−π6\displaystyle -\frac{\pi}{6}
Worked through
π6\displaystyle \frac{\pi}{6}

That angle has sine −1/2, not 1/2. Find the angle in [−π/2, π/2] whose sine is 1/2.

See the worked solution

Where it comes up

Practise against it

Each of these has an answer this slip gives. Work them on paper: if you fall into it, the verdict names it and the question comes back in review.

  1. 02
    Find the exact value of arctan⁡ ⁣(tan⁡3π4)\arctan\!\left(\tan\dfrac{3\pi}{4}\right).

    Implicit differentiation and inverse trigonometric functionsIntroductory

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