Senior-secondary mathematics task 71: What is the area of a circle of radius 8?
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Use the circle-area formula A = πr². Substituting r = 8 gives A = π × 8² = 64π.
Algebra, arithmetic, reasoning.
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Use the circle-area formula A = πr². Substituting r = 8 gives A = π × 8² = 64π.
Percentage=(11/26)×100=42.31.
Subtract 10 from both sides and divide by 2: x = (26-10)/2 = 8.
By Vieta’s formula, the sum of the roots equals the coefficient 17.
aₙ=a₁+(n−1)d=9+(12−1)×2=31.
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The sum is n(n+1)/2=10, so the mean is 10/4.
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There are 4 favourable outcomes out of 8 equally likely outcomes, so P(red)=4/8.
The coordinate differences are 3 and 4, so the distance is √(3²+4²)=5.
f′(x)=6x²+16x. Substituting x=3 gives 102.
An antiderivative is 3/2 x²+2x. At x=4, the value is 32.0.
The dot product is 3×2+3×1=9.
Rewrite the value using base 4: 256 = 4^4. Matching exponents gives x = 4.