Practice China questions with answers and explanations.
f′(x)=15x²+8x. Substituting x=2 gives 76.
Percentage=(13/28)×100=46.43.
Subtract 3 from both sides and divide by 4: x = (43-3)/4 = 10.
By Vieta’s formula, the sum of the roots equals the coefficient 6.
aₙ=a₁+(n−1)d=2+(14−1)×4=54.
Choose an option to check your answer.
The sum is n(n+1)/2=15, so the mean is 15/5.
Choose an option to check your answer.
There are 5 favourable outcomes out of 10 equally likely outcomes, so P(red)=5/10.
The coordinate differences are 3 and 4, so the distance is √(3²+4²)=5.
f′(x)=12x²+6x. Substituting x=1 gives 18.
An antiderivative is 1/2 x²+4x. At x=2, the value is 10.0.
The dot product is 1×4+5×3=19.
Rewrite the value using base 2: 4 = 2^2. Matching exponents gives x = 2.
