Quad polynomials help (1 Viewer)

[Munkiie]

I need help with these questions

1) find values of m such that mx^2 + 3x -4 <0 for all x

2) solve 5^2x - 26.5^x +25=0

Thanks in advance

 

[TimeGoesTooFast]

I'll just give you hints.
1) Use discriminant, which has to be less than 0 such that it has no roots.
2) let X= 5^x (it's reducible quadratics)- Solve 5X^2-26X+25=0

 

[TheMathStudent]

^Think you meant to say not 5x^2

 

[TimeGoesTooFast]

yeah my bad, was in a rush.

 

[asianese]

I think 2) was actually

. To solve this, let so that the equation becomes since

 

[SharkeyBoy]

therefore (u-25)(u-1)=0
u = 25,1
5^x = u
x = 0,2