Practice china-kaoyan-math-1 questions with answers and explanations.
The coordinate differences are 3 and 4, so the distance is √(3²+4²)=5.
f′(x)=15x²+6x. Substituting x=2 gives 72.
An antiderivative is 2/2 x²+5x. At x=3, the value is 24.0.
The dot product is 2×4+6×6=44.
Rewrite the value using base 3: 27 = 3^3. Matching exponents gives x = 3.
Choose an option to check your answer.
Use the circle-area formula A = πr². Substituting r = 7 gives A = π × 7² = 49π.
Percentage=(14/49)×100=28.57.
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 6 favourable outcomes out of 14 equally likely outcomes, so P(red)=6/14.
Rewrite the value using base 2: 4 = 2^2. Matching exponents gives x = 2.
Choose an option to check your answer.
Use the circle-area formula A = πr². Substituting r = 6 gives A = π × 6² = 36π.
Percentage=(13/48)×100=27.08.
