Question

Please guys please pllease

Answer 1

x= -3.936 and -0.064

Explanation:

I simplified the equation to 40u^2 +16u + 1. Then I just graphed it and found that the zeroes were -3.936 and -0.064.

Answer 2

`{ \qquad\qquad\huge\underline{{\sf Answer}}}`

Here we go ~

Let's calculate its discriminant :

`\qquad \sf  \dashrightarrow \: 4 {u}^(2) + 16u + 41 = 40`

`\qquad \sf  \dashrightarrow \: 4 {u}^(2) + 16u + 41 - 40 = 0`

`\qquad \sf  \dashrightarrow \: 4 {u}^(2) + 16u + 1 = 0`

Here, if we equate it with general equation,

• a = 4

• b = 16

• c = 1

`\qquad \sf  \dashrightarrow \: disciminant = {b}^(2) - 4ac`

`\qquad \sf  \dashrightarrow \: d = (16) {}^(2) - (4 * 4 * 1)`

`\qquad \sf  \dashrightarrow \: d = (16) {}^(2) - (16)`

`\qquad \sf  \dashrightarrow \: d = 16(16 - 1)`

`\qquad \sf  \dashrightarrow \: d = 16(15)`

`\qquad \sf  \dashrightarrow \: d = 240`

Now, since discriminant is positive ; it has two real roots ~

The roots are :

`\qquad \sf  \dashrightarrow \: u = ( - b \pm √( d ) )/(2a)`

`\qquad \sf  \dashrightarrow \: u = ( - 16\pm √( 240 ) )/(2 * 4)`

`\qquad \sf  \dashrightarrow \: u = ( - 16\pm 4√( 15 ) )/(8)`

`\qquad \sf  \dashrightarrow \: u = ( 4(- 4\pm √( 15 )) )/(8)`

`\qquad \sf  \dashrightarrow \: u = ( - 4\pm √( 15 ) )/(2)`

So, the required roots are :

`\qquad \sf  \dashrightarrow \: u = ( - 4 - √( 15 ) )/(2) \: \: and \: \: ( - 4 + √(15) )/(2)`