For cos(2x) * (2cos(x) + 1) = 0, use the double angle identity for cos(2x), which is cos^2 x - sin^2 x = cos^2 x - (1-cos^2) = 2cos^2 x - 1.
So we have (2cos^2 x - 1)(2cos x + 1) = 0. So 2cos^2 x -1 = 0 or x = 0 and 2pi.
For 2sec^2 x + tan^2 x - 3 = 0, use the identity sec^2 x = tan^2 x + 1, so we have
2(tan^2 x + 1) + tan^2 x - 3 = 0 or
<span>2tan^2 x + tan^2 x - 1 = 0 or
</span>3 tan^2 x = 1.
So x = pi/2, pi/2 + pi = 3pi/2.
Answer:
1. 7x
2. 8x - 1
3. 12 + 6x
4. 4 - 7x
5. 13x - 7
Step-by-step explanation:
2/3x-1/5=x-1
Add similar elements 23x-15=8x
Subtract x from both sides 8x-x=x-1-x
Simply 7x=-x
Divide both sides by 7 7x = -1
__ __. *Simply: x=-1/7
7 7
The length would be 90 cm. For every 1 cm of actual size it will be increased by 9. So.....10 x 9 = 90 cm.
