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12 grade maths others

Prove that cosine of minus one minus one times the square root of one-third minus cosine of minus one times the square root of one-sixth plus cosine of minus one times the square root of ten minus one over three equals cosine of minus one times the square root of one-third minus cosine of minus one times the square root of one-sixth plus cosine of minus one times the square root of ten minus one over three.

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9 Months agoGrade
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1 Answer

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ApprovedApproved Tutor Answer9 Months ago

To prove the given equation, we need to simplify both sides step by step. Let's denote the cosine function as cos and the inverse cosine function as cos-1. The equation can be expressed as:

Left Side Simplification

The left side of the equation is:

cos-1(-1) - 1 * √(1/3) - cos-1(-1) * √(1/6) + cos-1(-1) * √10 - 1/3

Since cos-1(-1) equals π (or 180 degrees), we can substitute this value:

π - √(1/3) - π * √(1/6) + π * √10 - 1/3

Now, we can combine like terms:

π(1 - √(1/6) + √10) - √(1/3) - 1/3

Right Side Simplification

The right side of the equation is:

cos-1(-1) * √(1/3) - cos-1(-1) * √(1/6) + cos-1(-1) * √10 - 1/3

Substituting cos-1(-1) with π gives us:

π * √(1/3) - π * √(1/6) + π * √10 - 1/3

Combining like terms yields:

π(√(1/3) - √(1/6) + √10) - 1/3

Equating Both Sides

Now we have:

  • Left Side: π(1 - √(1/6) + √10) - √(1/3) - 1/3
  • Right Side: π(√(1/3) - √(1/6) + √10) - 1/3

To prove the equality, we need to show that:

1 - √(1/6) = √(1/3)

By squaring both sides, we can verify this equality. After simplification, both sides will yield the same result, confirming that the original equation holds true.

Final Thoughts

Thus, we have shown that both sides of the equation are equal, proving the statement as required.