Solve the equation 36x4 13x2 10 Solve the equation Solve th

Solve the equation. 36x^-4 - 13x^-2 +1=0 Solve the equation Solve the inequality (x+2)(x- 6)(10-x)

12. 36x^-4 -13x^-2 +1 =0

Let x^-2 =y

36y^2 -13y +1 =0

Solve byusing quadratice root formula:

y = ( 13 +/- sqrt( 169 -36*4))/72 = ( 13 +/- 5)/72

= 18/72 , 8/72

= 3/8 , 1/9

y = 3/8 ---> x^-2 = 3/8

x^2 = 8/3 ----> x = +/- 2sqrt(2/3)

y = 1/9 ----> x^-2 = +/- 1/9

x^2 = 9 ----> x = +/- 3

13. {t/(t+1)}^2 -2t/(t+1) -15 =0

Let t/(t+1) = x

x^2 -2x -15 =0

x^2 -5x +3x -15 =0

x( x-5) +3( x-5) =0

(x+3)(x-5) =0

x =-3 ----> t/(t+1) = -3

t = -3t -3----> 4t = -3 ---> t = -3/4

x = 5 ---> t/(t+1) =5

t = 5t +5 ---> t = -5/4

15. x^2 < 25

(x^2 -25) <0

(x+5)(x-5) <0

Solution : -5<x < 5