Pure Math interview questions: page 3 of 3

Questions 101–111

101. Linear ODE with integrating factor x and y(1) = 1Easy
102. General solution of y'' + y' + y = 0Easy
103. Forced ODE y'' + y' + y with constant and linear right sidesMedium
104. Range of corr(y,z) when both correlate 0.8 with xMedium
105. Least-squares regression via QR factorisationMedium
106. Making two correlated normals from independent onesEasy
107. Counting climbs of n steps in strides of one or twoEasy
108. Hundredth decimal digit of a huge power of 1 plus root 2Hard
109. What asymptotic analysis does in quant modelsHard
110. Perimeter and area of the Koch snowflake in the limitMedium
111. Every integer divides some number made of 1s and 0sHard