1. We know that sin θ = cos (90° - θ) and cos θ = sin (90° - θ) Therefore, sin 67° + cos75° = cos (90°- 67°) + sin (90° - 75°) = cos 23° + sin 15° Explanation video🙌😀

    We know that sin θ = cos (90° – θ) and cos θ = sin (90° – θ)
    Therefore, sin 67° + cos75° = cos (90°- 67°) + sin (90° – 75°)
    = cos 23° + sin 15°

    Explanation video🙌😀

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  2. Given that: tan A = cot B ⇒ cot (90° - A) = cot B [∵ cot (90° - θ) = tan θ] ⇒ 90° - A = B ⇒ 90° = A + B Hence, A + B = 90° Video explanation 👇

    Given that: tan A = cot B
    ⇒ cot (90° – A) = cot B [∵ cot (90° – θ) = tan θ]
    ⇒ 90° – A = B ⇒ 90° = A + B
    Hence, A + B = 90°

    Video explanation 👇

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  3. Given that: sec 4A = cosec(A - 20°) ⇒ cosec(90° - 4A) = cosec(A - 20°) [∵ cosec(90°- θ) = sec θ] ⇒ 90°-4A = A - 20° ⇒ 90°+20° = 5A ⇒ 5A = 110° A = 22° Hence, A = 22° See this for better understanding😮👇

    Given that: sec 4A = cosec(A – 20°)
    ⇒ cosec(90° – 4A) = cosec(A – 20°) [∵ cosec(90°- θ) = sec θ]
    ⇒ 90°-4A = A – 20°
    ⇒ 90°+20° = 5A ⇒ 5A = 110° A = 22°
    Hence, A = 22°

    See this for better understanding😮👇

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  4. To verify that a given number is a zero(root) of a cubic polynomial, we can substitute the number into the polynomial and see if the result is zero. However, also the number is a zero of the polynomial, If the result is zero. See here the Solution 👀

    To verify that a given number is a zero(root) of a cubic polynomial, we can substitute the number into the polynomial and see if the result is zero. However, also the number is a zero of the polynomial, If the result is zero.

    See here the Solution 👀

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  5. Cubic polynomials can have one, two, three, or no real zeros (roots), depending on the values of the constants a, b, c, and d. For example, the cubic polynomial x³ + 2x² - 4x + 4 has one real zero (2), while the cubic polynomial x³ - 2x² + x - 1 has no real zeros. See here for Solution👇

    Cubic polynomials can have one, two, three, or no real zeros (roots), depending on the values of the constants a, b, c, and d. For example, the cubic polynomial x³ + 2x² – 4x + 4 has one real zero (2), while the cubic polynomial x³ – 2x² + x – 1 has no real zeros.

    See here for Solution👇

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