`(81x^(2)-81)-:(x+1)`

(x-5)^2-81=0

lim_ (x rarr (1) / (2)) ((x ^ (4) -81) / (x-3))

The complete set of values of a for which the function f(x)=tan^(-1)(x^(2)-18x +a)gt 0 AA x in R is a. (81, infty) b. [81,infty) c. (-infty,81) d. (-infty,81]

x^(4)-81 =____

Factorise the following 81x^(2)-121/49

Factorise : 64 x^(2) - 81y^(2)

If 3x - (1)/(3x ) =5 , find : (ii) 81x^4 + (1)/( 81x^4)

16x^(7)-81x^(3)-16x^(4)+81

Simplify (81x^(4)-16x^(2)+32x-16)/(9x^(2)-4x+4)