<span>x(3x+5)-4(3x+5)
3x^2+5x-12x+20
3x^2-7x+20</span>
Answer:
44
Step-by-step explanation:
6(8)-4 = 48-4= 44
cos a = 3/4
Step-by-step explanation:
Step 1: Given details are cos(a)^4 - sin(a)^4 = 1/8
Now, cos(a)^4 can also be written as (cos²a)² and sin(a)^4 can be written as (sin²a)²
⇒ (cos²a)² - (sin²a)² = 1/8
Step 2: Apply the formula for a² - b² = (a - b) (a + b). Here a = cos²a and b = sin²a
⇒ (cos²a)² - (sin²a)² = (cos²a - sin²a) (cos²a + sin²a) = 1/8
⇒ (cos²a - sin²a) = 1/8 since cos²a + sin²a = 1
⇒ cos²a - (1 - cos²a) = 1/8 since sin²a = 1 - cos²a
⇒ 2 cos²a - 1 = 1/8
⇒ 2 cos²a = 1 + 1/8 = 9/8
⇒ cos²a = 9/16
⇒ cos a = 3/4
Just look at where the 1 is at and then divide it by the place value. The 1 is in the thousandths place so the fraction would look like the following
