Practice China questions with answers and explanations.
The coordinate differences are 3 and 4, so the distance is √(3²+4²)=5.
Rewrite the value using base 4: 256 = 4^4. Matching exponents gives x = 4.
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Use the circle-area formula A = πr². Substituting r = 4 gives A = π × 4² = 16π.
Subtract 6 from both sides and divide by 5: x = (11-6)/5 = 1.
By Vieta’s formula, the sum of the roots equals the coefficient 13.
aₙ=a₁+(n−1)d=5+(11−1)×1=15.
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The sum is n(n+1)/2=28, so the mean is 28/7.
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There are 3 favourable outcomes out of 6 equally likely outcomes, so P(red)=3/6.
The coordinate differences are 3 and 4, so the distance is √(3²+4²)=5.
f′(x)=6x²+10x. Substituting x=3 gives 84.
An antiderivative is 3/2 x²+2x. At x=4, the value is 32.0.
The dot product is 3×2+3×1=9.
