Prove that C(9,4) = C(8,4)+C(8,3)

Verify that 2 C (7,4)= C(8,4) .

Prove that: (9pi/8) - (9/4)sin^-1(1/3) = (9/4)sin^-1(2sqrt2/3)

Prove that (9pi)/8 - 9/4 sin^-1 (1/3) = 9/4 si^-1 ((2sqrt2)/3)

Prove that (9pi)/(8)-9/(4)"sin"^(-1)1/(3)=9/(4)"sin"^(-1)(2sqrt(2))/(3) .

Prove that : sin^4 frac (pi)(8)+ sin^4 frac (3pi)(8)+sin^4 frac (5pi)(8)+sin^4 frac (7pi)(8)=3/2 .

Prove that .^(n-1)C_(3)+.^(n-1)C_(4) gt .^(n)C_(3) if n gt 7 .

Given that A (3, 2,-4), B(5, 4, -6) and C(9, 8, -10) are collinear. Find the ratio in which B divides [AC].

Prove that 1 + ^3C_1+ ^4C_2= ^5C_3 .

Prove that the points A(5,0,2), B(2,-6,0),C(4,-9,6) and D(7,-3,8), taken in order, form a square of area 49 square units.

Prove that: cos^4pi/8+cos^4(3pi)/8+cos^4(5pi)/8+cos^4(7pi)/8=3/2