Solve :
( i ) `( a + 7 )^3 - ( a - 7 )^3`
( iv ) `( 3x^2 + 1/x ) ( 3x^2 - 1/x )`

Solve: 3x^(2) + 5 = 7x

Simplify : (i) (5x - 9y) - (-7x + y) (ii) (x^(2) -x) -(1)/(2)(x - 3 + 3x^(2)) (iii) [7 - 2x + 5y - (x -y)]-(5x + 3y -7) (iv) ((1)/(3)y^(2) - (4)/(7)y + 5) - ((2)/(7)y - (2)/(3)y^(2) + 2) - ((1)/(7)y - 3 + 2y^(2))

Solve for x : (x+ 3)/(x + 2) = (3x -7)/(2x - 3) , x =2 , (3)/(2)

(7 ^ (2x + 3) + 7 ^ (2x + 1)) / (7 ^ (2x + 2) + 7 ^ (2x + 1))

Solve for x : (3x -2)/(5x + 7) = (1)/(12)

If y = tan ^ (- 1) ((1) / (1 + x + x ^ (2))) + tan ^ (- 1) ((1) / (x ^ (2) + 3x + 3)) + tan ^ (- 1) ((1) / (x ^ (2) + 5x + 7)) then y '(0) = (i) - (3) / (10) (ii) - (5) / (10) (iii) - (7) / (10) (iv) - (9) / (10)

(12x + 17) / (3x + 1)-(2x + 15) / (x + 7) = 3 (1) / (5), x! =-(1) / (3), -7

Solve: x-3=3x+7 .