Answer:
Step-by-step explanation:
c
Step-by-step explanation:
2x^2 + x - 28
= 2x^2 - 8x + 7x - 28
= 2x(x-4) +7(x-4)
= (2x+7)(x-4)
2x+7 = 0 or x-4 = 0
x = -7/4 or x = 4
20$...............................................................
Sin² x + sin x cos x = 0
sin x ( sin x + cos x ) = 0
sin x = 0 ; x 1 = k π ; k ∈ Z
sin x + cos x = 0 / ²
sin² x + 2 sin x cos x + cos² x = 0
2 sin x cos x + 1 =0
sin ( 2 x ) = - 1
x = 3π / 2 + 2 kπ / : 2
x 2 = 3π / 4 + kπ ; k ∈ Z
