Here is another way to work out E",-1r2. Observe that (r+1)3 -73 = 3r2 +3r+1. Hence E(r+1) -73 = 3 r2+3 E rtn. r=1 r=1 r-1 The left-hand side is equal to 2° – 1°) + (3³ – 2ª) + (4° – 3°)+.. + (n+1) -n°) = (n+1) – 1. %3D Hence we can work out 2=-1. Carry out this calculation, and check that your formula agrees with in ExerHUAWEI Nova 3i

part a to d. thank you

If r= dR dx which of the following is equal to R2R-¹r+2Rr (2²+R²)√(2²+R²) ²-1 -Arcsec(2² + R²) ? (R2R-¹+2R)r (2²+R²)√4²+R+-1 The answer cannot be found among the other choices. 2²rln2+ 2Rr (2²+R²) √√(2" + R²− 1) (2² +i 2 In2+2R (2²+R²) √√(2²+R²) ²-1 dx

a b c Question 6 : If A = d e f, with det (A) = 3. Find h i [49 2a -d] det (2B-1) when B= 4h 26 -e 4i 2c -f