Senior-secondary mathematics task 170: The roots of x² − 15x + 54 = 0 are r and s. Enter r+s.
By Vieta’s formula, the sum of the roots equals the coefficient 15.
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By Vieta’s formula, the sum of the roots equals the coefficient 15.
Subtract 9 from both sides and divide by 3: x = (24-9)/3 = 5.
Percentage=(9/34)×100=26.47.
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Use the circle-area formula A = πr². Substituting r = 8 gives A = π × 8² = 64π.
Rewrite the value using base 4: 256 = 4^4. Matching exponents gives x = 4.
The dot product is 3×4+6×3=30.
An antiderivative is 3/2 x²+5x. At x=4, the value is 44.0.
f′(x)=15x²+4x. Substituting x=3 gives 147.
The coordinate differences are 3 and 4, so the distance is √(3²+4²)=5.
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There are 6 favourable outcomes out of 11 equally likely outcomes, so P(red)=6/11.
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The sum is n(n+1)/2=10, so the mean is 10/4.
aₙ=a₁+(n−1)d=7+(7−1)×3=25.