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

Q: d²y Show that y = sin(2t) satisfies . + 4y = 0 dx²

A: 1) To prove the given equation 2) To find the value of w

Q: 10. Given: CH bisects ZDHG , mGF = (2x + 6) , and mDC = (7x – 1)'. E H C G F

A:

Q: 3 x° + Find + 3 . x6 x)dx - + C

A: Let's find integration of given function.

Q: Factor: 2x - 9x 5 main abc func DEG ab lal 8 9. 4. sin cos tan 1. 3. 0. ans O 2x 1 O 2x 5 o 2x + 1…

A: Topic = Quadratic equation

Q: (2) S dx x²√9-x²

A: Note:- Since you have asked multiple question As per our policy, we will solve the first question…

Q: what is written after 2xy - 2sin(y) in part i.

A:

Q: (c)(i) Use the substitution x = tan²0 to show that √x 。 (1 + x² ) ² (ii) Hence find in simplest…

A: We have to show                            ∫01x1+x22dx=∫0π42sin2θdθ     by substituting  x=tan2θ and…

Q: Calculate the resultant (i) V₁ - V₂ - V3 and (ii) V₂ + V₁ − V3 when V₁ = 80 N at 55° V₂ = 90 N at…

A: Given details: v1 = 80 N at 55ov2 = 90 N at 120ov3 = 110 N at 110o (i) v1 - v2 - v3 = 80 sin (55) i^…

Q: Select all the expressions equal to pr ry Op.z: (r· y) O (p - x) ÷r. Y Op z÷r.y Op: O (p r) ÷ (r ·…

A: The expression is given by p·xr·y

Q: 9. (9x + 25) (13x-19)/(17y + 5)',

A: label the points as: A,B,C,D,E,F,G and H.