← All NBT Flashcard Decks

NBT Mathematics: Trigonometry Flashcards

7 cards from real NBT practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

Read the first 7 NBT Mathematics: Trigonometry flashcards as text
  1. Express cos(180° − θ) in terms of cos θ.

    Answer: −cos θ

    Using the co-function reduction formula, cos(180° − θ) = −cos θ.

  2. The graph of y = cos x has a maximum value at x equal to:

    Answer: 0°

    y = cos x reaches its maximum value of 1 at x = 0° (and x = 360°, etc.).

  3. Given sin 40° ≈ 0.643, what is cos 50°?

    Answer: 0.643

    Since 40° and 50° are complementary angles, cos 50° = sin 40° ≈ 0.643.

  4. Solve cos θ = −1 for θ ∈ [0°, 360°].

    Answer: 180°

    cos θ = −1 only at θ = 180° within [0°, 360°].

  5. What is the value of 2sin 60° − cos 30°?

    Answer: √3/2

    2sin 60° = 2 × (√3/2) = √3 and cos 30° = √3/2, so √3 − √3/2 = √3/2.

  6. The graph of y = sin x is shifted 30° to the right. Its equation becomes:

    Answer: y = sin(x − 30°)

    A horizontal shift of 30° to the right replaces x with (x − 30°), giving y = sin(x − 30°).

  7. Using the Sine Rule, in triangle ABC if a = 10, sin A = 0.5, and sin B = 0.8, find b.

    Answer: 16

    By the Sine Rule: b/sin B = a/sin A → b = 10 × 0.8/0.5 = 16.