Question

4x2-15x-4=0 factorisation

Answer 1

$- 4 \times 4 = - 16$
$- 16 + 1 = - 15$
$4 {x}^{2} + x - 16x - 4 = 0$
$x(4x + 1) - 4x(4x + 1) = 0$
$(x - 4x)(4x + 1)$
are the factors
Hope this helps u ☺☺

Answer 2

Answer:

Step-by-step explanation:

α = 1/4

β = -4

Step-by-step explanation:

p(x) = 4x² + 15x - 4 = 0

Here

a = 4

b = 15

c = -4

Using Quadratic Formula or Sridharacharya Formula

x = -b ± (√b² - 4ac) / 2a

D = b² - 4ac

= (15)² - (4×4×-4)

= 225 - (-64)

= 289

Now,

√D = √289 = 17

Now

α = -b + √D /2a

= -15 + 17/2×4

= 2/8

= 1/4

β = -b-√D/2a

= -15-17/2*4

= -32/8

= -4

α = 1/4

β = -4

α+β = 1/4 - 4 = -15/4

α+β= -b/a = -15/4

Proved !

αβ= 1/4×-4= -1

αβ= c/a = 4/-4=-1

Proved !